1981 YT125 Stud Duck Questions

[generallee2005]

153820153821153822153823Hey guys, I'm a long time member, first post.

I recently entered the 3 wheel world with a 1981 yamaha YT125, called the Stud Duck. I've cleaned the carb, & am waiting on the air filter & the one bad gasket in the carb to arrive, in the mean time I am working on restoring the plastics & seeking advice.

The carb was decently clean, but I was missing the ends of most of the hoses, I have an idea of where most went by the manual most graciously provided by MonroeMike, & have them labeled as where I understand them to go. I tried to upload pictures, but all my photos with my digital camera were too big of the carb, so I'll do my best to be very descriptive. The two nipples on the side of the carb, almost right beside where the sleeve butterfly is, mine had no hoses there. Are they simply air vents? Also, the one on the bottom of the bowl, is this also just a vent?

Also, on the back of the lower motor, on the right side, there is a vent for a hose, that is almost completely broken off, my best guess is that this is a vent. Should a try to fix the hose fitting & run the hose to keep water out? The transmission oil had that milkshake look from water in the oil, but I don't know how long since it had last been changed & I believe the 3 wheeler lived outside & uncovered.

When it comes to the autolube, what is the best way to disable it? I've read the posts that say rip it out & JB Weld it solid, but I like having the option to reinstall at some point if ever a Pebble Beach style show comes around, so I can be as factory spec as I can. I plan on running the mix 40:1, any objections or opinions? I've seen the posts that swear by 32:1, which is best?


That is really the sum of my questions, except for does anyone know where a good aftermarket exhaust can be found for my Stud Duck? I've been searching the usual suspects to no avail.

Anyone know the photo upload size cut off? I can try to doctor my carb pictures, but I need a goal.

Thanks guys! I've done my best to use the search before a bonehead post, but if I missed one please be gentle!

Troy

[fabiodriven]

:shiftyeyes:Trailpros:shiftyeyes:

[generallee2005]

I noticed my wheels say TrailPros, duh.

[old-yellow]

Welcome to forum, don't worry about the vent on the lower right part of the case it just a place for gas overflow from the carburetor to go, As for your carburetor am having trouble picturing what your describing, am sure if you do some searching you will find your answers on here.

[generallee2005]

The two black hose fittings are the one I have questions about. The one on the right is pointing right to the camera & the one on the left is pointing almost straight up, they can twist, but neither had a hose connected.

Thanks again for the help guys!

153871

[old-yellow]

oh those are two breathers run two hoses and put the ends of the hoses up high, and as far as finding aftermarket exhaust that can be some what of a challenge, your best bet is two put a ad on here for one.

[generallee2005]

Got her running pretty good today! Got the old milkshake out of the trans with some ATF, and some new oil put in. Everything worked like a charm, except I have a busted seal somewhere in the exhaust side letting the oil out the exhaust. I really don't plan on splitting the case anytime soon, & obviously this is not ideal, but other than watching the trans oil level, is there anything else I should expect? My trans case says 750 ml, but when I pour in with the fill level bolt out, the oil almost immediately runs out of the fill level bolt hole, should I measure out 750 ml & pour in regardless of the oil full level? I do have a silly question, I got a small inline gas filter from AutoZone but the thing didn't have instructions. I'm assuming that the filter goes this way, so you can see the trash on the outside of the filter & know when to change, but once I put it on the carb poured gas out of the bowl overflow like no tomorrow. I believe the carb is clean, but going to clean again tomorrow regardless, & there has been clean gas going in the whole time, the filter was just cheap insurance.

158173

[Howdy]

That is how I would run the filter.
The Stud Duck was added buy someone who wanted to customize it.
If you need some good plastics let me know. I know I have a nice rear fender. and I would love to find it a new home. LOL
Howdy

[old-yellow]

you have the filter the right way as far as the oil i fill mine until i see oil flow out the lower bolt of the trans cover. here's a link to a manual http://www.oscarmayer.net/atc/manuals/Yamaha/ytm-%28yt125,yt175%29condensed-service-data.pdf

[old-yellow]

the manual will also allow you to set the float in the carb, any pics of the exhaust leak your talking about, how about pics of it cleaned up and looking good?

[fabiodriven]

I'll never understand why it's almost everyone's first move to disable the oil injection.

I'd like to see a pic of this oil leak as well. You've got me a bit confused on that one.

The oil may be blowing out of the level check-hole before it has a chance to settle into the rest of the transmission. I'd fill it from empty with 750ml and let it sit for a bit before checking it again.

If gas is pouring out of your carb, tap the bowl with the handle of a screwdriver to get the floats working again.

[generallee2005]

Those were 2 questions, for the trans oil fill level, I'll pour the oil in & let it settle longer before checking the fill level with the bolt. As far as the oil leak thru the exhaust, here's a picture of it, this was before my axle bearings came in, so its an older picture where the bike had just been idling & ran maybe 2 minutes. I didn't take any picture of the oil leak after I had gotten it up to temperature because I had to load up & get home quick. You can see the oil drip on the concrete below the exhaust.

Thanks Howdy for the offer on the rear fenders, I've stripped the fenders & am putting the finishing touches on the polish job. Right now I'm going back & getting the spots I was to impatient enough to get out up to my standard the first time! All that wet sanding has taught me patience if nothing else! I did have to get a new seat pan, which is painted & ready to go, all I need there is a new seat foam & a seat cover, & a new tail light now, my other one got busted somehow while I was riding Tuesday.

158266

[old-yellow]

hows the stud duck coming along?

[generallee2005]

Here's a few pictures of my plastics & seat pan. I've still got to put the finishing touches on the polishing job on the front fender & headlight cover, but the rear fenders turned out good. I've got the gas tank cover at work getting wet sanded when the time is right, I've still got to put the black stripes on it. Everything is basically ready, I'm just trying to decide if I want to get the oil out of the tailpipe problem solved. I've been talking to a coworker who used to be into dirt bikes & he knows a guy that works on the motors, but at $35 an hour, I don't really want to be into this little machine too much. I believe that since I'm getting 90 psi of compressions if I open up the motor, I may as well do a rebuild, but I'd rather get the 250R running. So far I'm only in $100 for cables, the seat pan, & all the little odd & ends. The oil leak is making the spark plugs foul every time its running it seems.

158674158675158676158677158678

[generallee2005]

That fuel filter picture just popped in, oops. That's also what the spark plug looks like after only about 15 minutes of running, dripping with oil.

[old-yellow]

its not that hard to replace the crankshaft seal if you need help doing it i am more than willing to talk you through it. also are you running premix or oil injection

[generallee2005]

Made the switch to premix after I'd taken the previous pictures, I've blocked the oil injector, but I haven't taken the pump off yet. How would I replace that crankshaft seal? I wouldn't be as hesitant if I had a garage or somewhere inside to work on the motor, working in the front yard isn't ideal. I'm deathly afraid of opening a new can of worms, but I guess that's part of this ball game.

[old-yellow]

heres a link to a manual look in engine overhaul section under right side cover removal http://www.oscarmayer.net/atc/manuals/Yamaha/ytm175_82-83_tri-moto_manual.pdf it will show you how to pull the side cover off and pull the clutch out so you can get to the primary drive gear to remove it and right behind that is the crankshaft seal you need to replace. if you have any questions let me know

[old-yellow]

when you go to put it back together there's eight ball bearings that are in the clutch, to keep them in place tip the motor on its left side, also make sure you keep all the clutch disks and plates in the order they come out

[generallee2005]

I'm gonna be crazy enough to try it, I've got the week before Christmas off & I guess I'll get a drop cloth & rebuild it in my office! My wife is going to be pumped! I'm going to get the Athena Complete Engine Gasket kit from bikebandit.com, anything I should keep an eye out for? I'll have lots of questions I'm sure. Will I really need the flywheel holding tool, & a crankcase separating tool? I suppose I can find them on the web too, but would like to keep costs down. While I'm knee deep in, anything else I should keep an eye out for? I guess I'll accept & budget for a new piston or rings if needed.

Also, the manual link is for an 82+ YT175, I suppose they'd be relatively the same, right? Or at least close enough for government work.

[old-yellow]

you wont need a flywheel holding tool if you a air impact and as far a splitting the case the crankcase separating tool makes it a hell of a lot easy to do, but i would try when you get it tore down to the crankshaft seal i would trying using a small hooked pick between the crankshaft and the seal and try and hook the seal and pull it out i have done this and got it to work but some times the seal is pushed to far in and it won't come out or there to tight and won't budge so then i have to split the cases to get the seal. Make sure you leave the clutch disks and plates in the exact order they come out, as for the manual the YT175 motor comes apart the exactly the same way as the YT125. if you got more questions let me know.

[generallee2005]

Got any tips on removing these old Yamaha Phillips head screws? I've drilled out far too many!

[generallee2005]

So I got the old gasket exposed, but the kit I got wasn't exactly what I thought it was, so I'm on the hunt for the right seal. The seal looks good, but it is pushed in on the bottom, but while I'm in there I may as well fix it right.

159416

With the milkshake that was in the transmission I was surprised how clean it was inside.

I was going to replace more of the seals since I've got the gaskets, but after 4 of the 5 screw heads stripped out trying to get the case from behind the pull starter, I think we're in GOOD shape there!

[old-yellow]

sorry i should of told you about use a hand impacted on the screws it makes a hell of a lot easier and yes if i went that far i would just change it for piece of mind. but that's just my 2 cents. if you need help finding any of the gaskets let me know.

[generallee2005]

Got one on the way from eBay, but with the slowed down shipping from the holidays, my jets are cooling. While I'm in, is there anything else I should look at as a potential problem? A few of my clutch plates had small speckles of surface rust, should that be a concern?

[old-yellow]

i would clean it up with a little steel wool and as long as its not pitted i would not worry at all. check out your clutch basket for any groves cut by clutch plates and make sure you keep those clutch plates in the order you pull them out in.

[generallee2005]

Got the seal in the mail today, & an email with this "Also I wanted to let you know that the listing gives part number 93102-25144-00 but shows a picture of part number 93103-25125-00. These are both the same part for the same Bikes. One number supersedes the other. I apologize for the confusion in the listing."

The first thing I did was hold it to the old seal still in the bike & the new one seemed a little small , it didn't want to slide onto the shaft real good, but I'm assuming it won't without lube & a little persuasion. Hopefully I can put it in tomorrow trouble free & button it up, as long as my wife stops finding "better" ways for me to spend my vacation.

[old-yellow]

are you sure they sent you the right seal

[generallee2005]

According to the numbers wrote on the Ziploc bag, haha, it's the right one. I'll look closer tomorrow morning when its still light out, I was in a rush tonight just to check it, we had to go see Santa tonight. I had trouble before finding the front sprocket because of the supersession of part numbers, but the daylight will reveal all.

[generallee2005]

The right seal should be here Friday, so it'll probably be a while until I can get it put in & put back together. I'll be back to the grind after Christmas.

[generallee2005]

Had a little time to mess with the seals today, I pulled the old one out & found its measurements to be SW 28-40-8, the new seals size is SD 25-40-8 & is in the Yamaha bag, with the correct part number (93103-25125-00) according to http://www.cyclepartsnation.com/oemparts/a/yam/50038818f870021f60a09863/crankshaft-piston-yt125g-h-j

What is the difference between SW & SD, on the link both are part #17 & what will make a $3 difference.

I typed in the measurements off my original seal into eBay & got a search that listed many other machines, but no yt's. According to the auction, the measurements fit "FITS LEFT ON SOME AND RIGHT ON OTHERS. DT80 1983 (RIGHT SIDE), GTMXD 1977 ( RIGHT SIDE), IT175 1982-1983 (LEFT), YZ100 1977, 1982-1983, YZ125 1982-1985 (RIGHT SIDE), YZ60 1983, YZ80 1982-2001 (RIGHT SIDE).

NEW OLD STOCK OEM PART #93103-28126-00. 1- NEW LEFT SIDE CRANK SEAL. MHSD 28 X 40 X 8. "

My cylinder does say 123cc on the side, & I've checked the vin to find out the year, so what's up?

[old-yellow]

i have never ran into the problem you have, i always order my crankshaft seals from http://www.yamaha-motor.com/partviewer/default.aspx?ls=sport#/Yamaha/YT125K_-_1983/CRANKSHAFT_-_PISTON/YT125K_%281983_ALL_TERRAIN_VEHICLE%29/CRANKSHAFT_-_PISTON_%28YT125K_-_1983%29 or bikebandit with no problems and yes i know it says for 1983 but there the same seals used for 80-82 YT125's Yamaha just doesn't show them for 81-82 YT125's and as far as the difference between the seals if you look at this chart http://www.arai-net.com/products/product01e.pdf it will help explain the difference between SD and SW type seals, you need to use a SW type on the clutch side because there's oil and can use an SD type or SW type on the flywheel side because it don't have oil Yamaha recommends a SW type in there listing for 1983-1985 just because its a better sealing seal. I recommend you get both seals out and look at them so you know what your looking at then look them up and order them from Yamaha directly or bring them to your local Yamaha dealer and have them order them. i hope this helps

[old-yellow]

by the way the cyclenation sent you the way wrong trailprotrailprotrailprotrailpro so i would get your money back

[generallee2005]

With the Yamaha site, what I actually have is the wrong side seal. Time to reorder! Thank you for the links, I do see the difference between the seals construction now.

Here's another picture of my 250R, its actually an 81 because of the drum brake on the back, but it'll sit on ice at my grandma's barn for a while. I found out a couple of weeks ago I got into optometry school in Philly, PA! I still have more interviews to go though. The cylinder is in the bucket & the pipe is too the side, the fenders are out of picture. My wife sees junk, I see a blank canvas.

160204

[generallee2005]

Alrighty, I got the old girl put back together finally! Everything worked great, started up on the second or third pull, idled beautifully. Then I climbed aboard & shifted into 1st gear, it lurched forward like they do when put into gear, I gave it gas and nothing but a rev, just like in neutral. Ok, a minor set back I thought, I shifted to second, same thing, a small lurch forward when it went into gear & nothing but a free revving motor. All the gears were like this, then the motor stopped & I guess it had flooded out because I couldn't get it to start again, but honestly after fiddling with it all day & no victory ride, I was somewhat disgusted. I think it may be just that I don't have the clutch set up properly, but how do I go about troubleshooting this? I know the first time I had buttoned everything up, I tightened the little bolt with the 2 lock nuts, that you see when you take the case cover off where you put the transmission oil in, & that wouldn't let me change gears, so maybe I made it too loose?

Another question, I think my needle is sticking because sometimes gas just flows out of the overflow in the back of my carb. Everything is clean as a whistle, is there anyway to stop this? Maybe buff it out with some, I dunno, 1000 grit sandpaper or something? It usually stops with a light tap on the carb to loosen everything.

[generallee2005]

Anybody have a good trick to cleaning a petcock? Mine is filthy, I've got it soaking in mineral spirits, the spirits won't hurt the rubber & should dissolve the gunk slowly. Then I think run a pipe cleaner from the kiddos arts & crafts bucket through it. I liked the little bitty filter that was on the reserve pick up, good idea 30 years ago.

I did adjust the clutch today, but the carb wasn't getting enough gas which lead to me taking the petcock apart. I should know if this works out tomorrow afternoon if all goes to plan!

162241162242

[old-yellow]

i just soak mine in gas then use pipe cleaners and compressed air, it kinda sucks i just tried looking for a replacement filter but you cant get them i thought you still could.

[generallee2005]

I think I need a new carb, new carb is about the same price as a piece by piece rebuild thru bike bandit. I'm thinking going with this one http://www.bikebandit.com/mikuni-round-slide-vm-series-carburetor?m=147129, I see that the 125's have a 20mm carb. Would there be any advantage to going with a bigger carb for just a machine to tootle around on & pop wheelies? On second thought, I don't think I want the headache of finding a new intake boot & boot for the air filter, but I can be persuaded.

With the carb I have now, I've taken it apart, cleaned soaked, & blew air thru it at least 5 times. Still once it cranks it idles for a bit, but once you give it a chance the motor dies & won't start back for 20 minutes at least. I've got good spark, excellent gas flow, & a brand new Uni air filter. Maybe the ethanol gas sitting in it, before I got ahold of it, ruined the carb.

[Highhorse78]

I would check and verify that your float level is set correctly. Could be starving it of fuel. Also make sure nothing is blocking the breather in the gas cap.

[old-yellow]

i just re-read the whole thread to refresh my memory and try and help more but this is what i came up with, check the float just like highhorse said to make sure its not making it run rich and staling the motor and i dont know if what am thinking is correct or not on this, but are you still missing the baffle out of the exhaust that could be messing with the back pressure in the pipe and throwing off how the exhaust scavenges the air-fuel mixture into the cylinder.

[Honda250RinNC]

i bought a brand new in box carb on ebay for $34 its the same size as a blaster carb. if u want a link let me know..it works great

[old-yellow]

and no i would not go with a bigger carb because you would have do plug chops to get the jetting right for the bigger and that can get very time consuming and start to run you up on money and when you can go with stock and save the hassle. not worth it to me anyways

[generallee2005]

I'll check the floats, on Friday morning, a little closer before ordering a new one. I know the gas tank breather is good, I've drained the tank a few times without taking the gas cap off & it drained fast & with steady flow. Where would the baffle be in the exhaust pipe? I had the pipe off while I changed the crankshaft seal, & looked at the pipe out of curiosity pretty good, but I don't remember seeing a baffle. Would I be able to see it easily? I imagine it would be close to the front of the pipe.

Again, I want to thank all of you guys that have taken the time to help me out!

On a side note, this may be a silly question (but the only silly question is one not asked) is there a difference between a 2-stroke carb & a 4 stroke carb? Thanks for the offer Honda150RinNC, but at the moment I'll pass.

[old-yellow]

the baffle is at the back end of the pipe. here's a exploded view part #19162550 the thing is when i got my yt125 mine was missing too, but it ran and drove just had no top end power, sometimes when i would get on it, it would fall on its face and die also so am not a hundred percent if am right on it being the baffle making it act like its is. i am a little stumped on whats going on with it so hopefully some 2-stroke gods will jump in and help

[old-yellow]

here's your pic and thats162552 how i know your baffle was missing

[Highhorse78]

You could also have an air leak somewhere around the intake or the ignition (left) side crank seal. Does it run any better with the choke on? Did you end up putting new seals in? You can awlays check for air leaks by taking a propane torch with a rubber hose on the end and cracking the valve (DONT LIGHT), moving it around any suspected areas. It will idle up when a leak is detected.

What puzzles me most is that you say it wont start for at least 20 min. Did you ever get your carb to stop overflowing?

[generallee2005]

That's correct, I've got no baffle & they're not available on Bike Bandit, I'll have to scour the web tonight after work. I adjusted the floats & BOOM! She ran like a top! for about 50 yards. Then the clutch locked up, I can't get it to come out of gear. I guess I didn't have the lock nuts tight enough together on the clutch adjustment, the outer nut spun until it almost came off, the inner tightened down so tight that I cannot get it loose. I think I buggered up the threads on the adjustment bolt to bad too reuse with new bolts trying to get the nut off. I still haven't gotten it off yet. Any suggestions? Where I'm at now I really don't have access to an air gun. Those adjustment bolts aren't available on Bike Bandit either, so I guess I'll search high & low for one of them also. Maybe there are other years or models that will work? Maybe someone has them just lying around, I'd love to swap some cash for them!

Number 20 is the bolt I messed up, & I'll need the bolts also, #21. http://www.bikebandit.com/houseofmotorcycles/1981-yamaha-tri-moto-125-yt125h-shift-shaft-pedal-yt125h/o/m147129sch222747

[generallee2005]

Just ordered the bolt of eBay, I'll get round up some nuts once it gets here. Still on the search for the exhaust baffle/silencer, the only one on eBay is a NOS for a cool hundred bones. Not in my favor there, I'll also post up on the classifieds to drum one up I hope!

[generallee2005]

It rained all day here on Fat Tuesday, so no parades downtown for us. I decided I'd button up the clutch & I'll let the picture show.

162974

Our 10 minute splash through the subdivision gave me the motivation to finish sanding the plastics & finally make it complete, I'm shooting for Friday. All I need is a good lead on a new seat. I called Hi-Flite today, they don't have the pattern for the YT's. I'd like to have a desert style seat to ease things on the backside. I've got a re-done seat pan, just no good foam or cover. Any suggestions? I PM-ed Mrs. Mosh last Friday, but so far no reply.

[old-yellow]

am glad to here there's progress and i would try posting up a thread in the ATV classified's on here for the missing parts you need. also when it comes to seats there is two different styles, the 80-81 are alot thicker foamed and wider, the 82-85 are not as thick or as wide (they both mount the same onto the rear fender), but be careful when you go to order a seat cover that you get the right year to match whatever year seat you have. here's a link to ebay and there was some seat covers and complete seats that had okay looking seat pans.http://www.ebay.com/sch/i.html?_trksid=p3984.m570.l1313&_nkw=yt+seats&_sacat=0&_from=R40

[Highhorse78]

If youre still looking for an exhaust, I have one from a YT175 that should work. I would let you have it for the price of shipping (maybe $30). It needs to be cleaned out, wire wheeled/blasted and painted. You also need the flange and spring that bolts onto the jug, which I might have somewhere.

Heres a link to what needs to be done to mount the 175 exhaust to your 125- http://www.3wheelerworld.com/showthread.php/129972-Moto-Mods

[generallee2005]

Thanks HighHorse78, if I hadn't of already got the new silencer for the 125 pipe, I would have for sure taken you up on that!

[generallee2005]

Alrighty, I've got my new to me silencer in & I'm trying to take the baffle out of the back of it for inspection & maybe repacking while I've got it off the machine. The baffle feels welded in. Has anyone ever been successful at getting them apart without scarring the exhaust exit hole? I had it soaking in gasoline throughout the day today to see if it would loosen up, any other ideas or suggestions? Also, are these repack-able?

[old-yellow]

you can try heating the outside of the silencer to see if the baffle will loosen up (use propane torch) out and yes these you can re-wrap the baffles they use wrap around fiberglass silencer packing sheets

[generallee2005]

Getting the seat made by Mrs. Mosh! That will be back soon & we'll have a full fledged runner!

I do need a front tire though, the old trailpro that is there just won't hold air. Any suggestions? I'm thinking of getting 3 new ones, but will likely just get one, depends on the funds really. As far as riding type, I'll likely go thru it all except sand & snow. It doesn't snow much here in Alabama & we only have clay, no sand! Truth be told, I'm a little more interested in a good looking tire since this will likely just be for my son & me to toodle around the yard fields close by more than anything, nothing aggressive. I'm a firm believer in David Lee Roth's quote "it's not whether you win or lose, its how good you looked!"

I like these, http://www.bikebandit.com/maxxis-m9209-all-trak-atv-tire, but I need some help, I think I'd want the 2-ply for shock absorption, but it seems the more economical tires are all 2-ply. I want something that's going to hold up, but not have any give like the old stiff trailpro does. Is this a good tire for the front? Or would I need something that looks to have more side-to-side bite vs. rotational bite? Maybe I'm over complicating things, but all if I didn't value others opinions I wouldn't ask!

[Highhorse78]

I'm glad to hear your project is coming along nicely. For a front tire, I've been really impressed with Kenda's Front Max. Seems to stick to about everything , and doesn't allow the trike to be "pushed" around so easily when turning at slower speeds. I had one on my 200S and liked it so much, I might put one on the YT.

[generallee2005]

I'm needing some help adjusting the clutch. I've got the inner nut finger tight, & the lock nut tight against it, but when I get in the upper RPM, or when I put the spurs to it, the clutch slips. Idling along, the clutch does right, & really all the time unless I'm really trying to get there quick or am in a higher gear trying to speed up. This means no wheelies, so no fun!

I had tightened the inner nut maybe a full turn to turn & a quarter on the adjustment & the slipping seemed to get worse. I've got a little room to loosen the nuts. Is this backwards like that? Tighter nuts = looser clutch?

[old-yellow]

The repair manual says to adjust the clutch by adjusting the release mechanism by tightening the inner nut until the bolt can't be turned with your fingers but has no thrust play (in-and-out). Tighten the outer nut against the inner nut . If the bolt is too loose, the clutch will drag. If it is too tight, the clutch will slip. I hope this helps.

[Highhorse78]

The repair manual says to adjust the clutch by adjusting the release mechanism by tightening the inner nut until the bolt CAN be turned with your fingers but has no thrust play (in-and-out). Tighten the outer nut against the inner nut . If the bolt is too loose, the clutch will drag. If it is too tight, the clutch will slip. I hope this helps.

There :D

If this doesn't help the next thing I would look into is the clutch springs. Check their unsprung lenght... Should be no less than .60"

Also, are you using a trans oil specified for wet clutches?

[generallee2005]

I think I got the clutch worked out right, after finger tightening the inner nut, I backed it out 1/4 of a turn. Seemed to work great, I could cut doughnuts, & pop it up as best as I could without a seat or fenders. Then I noticed the brakes weren't working. UGH. Loaded it up & brought it home. Nothing more frustrating than that! I might have to adjust the clutch just a bit more, as I noticed when in the upper gears when I let off the throttle to upshift & then got back into the throttle, it seemed to be slipping then. Once I let off the throttle & eased back into it a little more gently it seemed to gradually catch & accelerate. Then I noticed the brakes weren't working. UGH. Loaded it up & brought it home. Nothing more frustrating than that!

When I'm adjusting the clutch, should everything be up to temperature or will this make a difference?

What exactly happens when a clutch drags? What mine is doing is when I'm in the throttle, the motor just seems to free rev, with no pull what so ever.

My brakes were working beautifully until I put on new handlebars, that were a little shorter, so now I have extra brake cable for the handbrake. Although the brakes wouldn't lock up before, I assumed it just needed a bit more adjustment, but since I could slow down decently I never gave it much thought. Now it seems that neither my hand brake or foot brake has the adjustment to take up the slack that I need gone to make the brakes work. In fact the foot brake hits the skid plate & the hand brake hits the handle bar grip before any woah it applied, & once the hand brake is released, it does not return to the normal position, it just stays where its left, the foot brake does because of the spring. Any common problems I should look for? I haven't inspected the brakes yet, just unloaded & carefully parked when I got home.

It was an eventful 2 hours of stud ducking today! Mrs. Mosh also sent me the art work for my seat, I can't wait, so close!

[Highhorse78]

For the rear brakes, there's a stud with a jam nut in the caliper that is used to adjust the pad clearance. Once you adjust that, adjust the cable itself to get your lever/pedal throw. See if that helps any.

[generallee2005]

I'll do that first, I did just realize looking at the bike bandit schematic that I don't have the return spring on the perch at the caliper. With the kiddos birthday Saturday this may be a good project for Easter Sunday for us to look at.

[generallee2005]

Got the brakes going a few days ago. Still feels like the clutch is slipping a little bit too much. What kind of oil do y'all prefer? Right now I've got Castor SAE30 in the crankcase.
I've been doing some searching here about clutch setup/tuning, from the sounds of it my centrifuge clutch is good, since I've got the clutch slipping a little throughout the start until its up & running. Right?

[old-yellow]

I run castor gtx 10w30 in mine with no problems, but as far as your clutch slipping when does it happen when you take off or when you are getting on the throttle at speed, just make sure that you have the clutch adjusted right if you still cant get that to work, you might have to pull the clutch side cover off and check the the friction plates and metal clutch plates with a digital caliper to make sure that there all within spec, the friction plates thickness new 0.090in (2.4mm) to used service limit 0.080in (2.1mm). Next check the metal clutch plates for warpage on a flat surface (i use a thick piece of glass for any flat surface work) with a feeler gauge they are allowed 0.002in (0.05mm) of warparge at any given point. remember do not mix the order of the friction plates and metal clutch plates up. Had to pull the specs for this out of my Haynes paper manual because the link for the online manual that i gave you before does not have the specs on this dont know why. you might want to pick up a Haynes they helpful as hell.http://www.amazon.com/Yamaha-ATVs-Owners-Workshop-Manual/dp/185010154X/ref=sr_1_1?ie=UTF8&qid=1365998770&sr=8-1&keywords=haynes+yamaha+manual+three+wheeler i have never had a bad YT clutch so this is all new to me to. good luck Alex

[old-yellow]

just stole this info from pat AKA vealmonkey so it might be a little harder then i was thinking to fix this.

What year is your 125 engine? If your 125 engine is 80 or 81, that clutch pack doesn't use as many clutch plates and friction plates as the 82 and later clutch pack. Don't ask me why, it just is that way. Also, I found out that yamaha used different thickness clutch plates. The total clutch pack has a tolerance for thickness that is made up by using the different thickness clutch plates, neato huh? If your clutch pack ends up too thick, it won't fit right into the clutch basket and you won't get the large steel clip in to hold it all together. Too thin, and either your clutches slip or your steel ring can pop out, once again, neaty petey! And then you have the 80-81 clutch pack that uses less clutch plates and clutch frictions-ARRRRGGGGHHHH! If you don't have a manual, you won't know this. That's why I always recommend a factory manual to anyone that has a trike, not an off brand manual, a factory manual. And be happy that it's not a Tiger or Rotax manual, what a piece of work they are. According to the manual, you should have 8 clutch frictions and 7 clutch plates, for the 82 and later clutch basket. The earlier 80 and 81 clutch basket has less. There are alot of dimensional measurement tolerances, too many for me to type them all out. And my manual is showing only 8 balls, but there are no mention of the number of the balls in the manual! Also there is an adjustment gap between the last clutch friction and the outer clutch plate that has the clutch springs in it. The manual says if you don't have the proper gap, that is when you have to mix and match the clutch plates. This is why you need a manual. Like I said, there are alot of measurements that you have to refer to a area to get them all. Also you would have to use a set of dial calipers to check the thicknesses of the clutch plates. You should also use a dial to check for the clutch spring "free length" and the length of the outer tiny springs of the clutch pack. Precise measuring is required here, much more so than other clutches I have had the oppurtunity to work on. That is why I have manuals, no way to remember all this info. You might have several problems with measurements being out of tolerance, parts just worn beyond their tolerance. If you have weak clutch springs, that will help your clutch slip too. It looks like you may have to pull the clutch all the way back apart and start over with alot more attention to detail. I might have to do this with my buddys yt125 also-Yay. Oh well, live and learn again. I thought we had it put back together right last time, but the third time is a charm, right? LOL heres the link to the thread i stole it from http://www.3wheelerworld.com/showthread.php/93969-Trimoto-125-175-clutch.?highlight=yt+clutch

[barnett468]

Hello


“The transmission oil had that milkshake look from water in the oil, but I don't know how long since it had last been changed & I believe the 3 wheeler lived outside & uncovered.”

The centrifugal clutch takes the brunt of the wear so it typically goes first.

I’m coming late so please excuse any duplicate questions.

The water did not help your clutches it could have trashed them.

Is it too expensive for you to simply replace both clutches?

Did you replace either clutch?

Were they replaced with Barnett’s, Japanese or Chinese?

Depending upon your std clutch design you can often pre-load the springs a little to reduce slippage by using either metric or AN washers or SAE, maybe .020” thick If you do that and slippage is same then centrifugal clutch is the only problem.

Oil should be oil designed for a WET clutch. Available at ALL motorcycle shops. The other will "work" but is not the best and since you have a clutch problem why take chances?

[generallee2005]

I don't mind duplicate questions, they make me go back & rethink what I've done. That is never a bad thing, I try to be 100% on all that I do, but I know I get in a hurry from time to time. This machine has lasted 32 years, I'd like to see it last double that.

Its not necessarily an expense thing as much as a time thing, I'm about to move & start grad school, so I'd just like to putt around in the yard & go riding on occasion before I leave the area. I have not replaced any clutches. The reason I took them off/out is to change the crankshaft seal behind them. I'll stop by & get some oil & try to tune the clutch again. It keeps getting better every time, so perhaps I learn a little more each time!

[barnett468]

Hello

Yes, perhaps the correct oil MIGHT give you slightly less slip. Either way it is best to use. If you fail to fix as I suggested just replace them both, doesn't take much longer than just doing one.

[generallee2005]

I think I got my clutch issue licked! Tomorrow is the day the plastics go on for a good buffing with the car buffer, then I'll wait patiently for my seat to arrive!

I had to just turn the adjustment screws an 1/8th of a turn until I like the way it felt. In 4th gear, it still kinda felt like it wanted to slip, but I can live with it until I have time & funds to build it good. I did put in the Yamalube 10w-40, guy at the Yamaha shop told me let that oil sit in for a couple of days & it would either solve my problem, or let me know its time to replace everything for sure.

I did take these pictures of the spark plug, since today was the real first time when I've rode the Stud Duck for at lease a solid 45 minutes. This is what the plug looked like when I cut the motor in a rev. What do you guys think? I think it looks good, but I'm a first time double stroker.

168163168164

[generallee2005]

New clutch discs & springs are on the way. I rode the duck yesterday & just wasn't satisfied.

[generallee2005]

Discs & springs arrived today, springs were beautiful. Wrong discs!! Curse you eBay!! I did find this out after impatiently soaking them in oil before cross checking the part numbers.

[old-yellow]

sorry to hear good luck to you

[generallee2005]

I was messing around with the pressure plate, decided while I've got some time waiting on the right discs, I'd replace the little bearing in the middle, since it felt rough. Also, I've got this lock washer that I thought I knew where went. The more I think about it the less sure I am about the washer, so two questions. I tried to push the bearing out with my hands, but it didn't move. What's the best way to get this little guy out? Then, does anyone know off hand where this lock washer goes? I can't find it in my manuals, or in the schematics.

I feel I'm so close to whipping the Stud Duck into shape I can taste it!

[generallee2005]

My my my. Bike Bandit sent me the same kit as the eBay store did. EBC CK2303 is what they are sending me, it has 6 discs, I need 7. The inner diameter where it mounts to the gear are right, but the outer diameter is too small. More google-ing is in store I suppose.

[generallee2005]

169918

Done! Minus the decals.