do I really need to wait 2 months to post in the tech forum?

[airbats801]

Swear to f;n god I use to have an account here, and had one on 3wheelers.org for eons.

own
81 250r
84 250r
85 110
84 110
86 125m
85 250sx
80 something yt125


Anyhow, gonna post here. Anyone know what healthy compression for a tri moto 125 is? My old one had about 90 when it just wouldnt go no more. THe current one I have has about 120ish. I'm curious of what they usually are after a new piston and ring.

GOt a hell of a deal on the ol girl though, 50 bucks lol. Had it started for a few secs with some ether, but then nothin. I dont have time to csi it yet, and I just picked up a airfooler 84 250r last night with a bhg I gotta csi. Maybe tomorrow night.

Been thinking about changing over to the tri moto for the extra umph over my 110 as my prefered trail bike.

[El Camexican]

This might help.

http://www.3wheelerworld.com/showthread.php/52186-Tri-Moto-125-hard-to-start-115lb-compression

[airbats801]

125 seems s low considering a 250r is around 180, but hell I wont trailprotrailprotrailprotrailprotrailpro if its that good lol.

[El Camexican]

125 seems s low considering a 250r is around 180, but hell I wont trailprotrailprotrailprotrailprotrailpro if its that good lol.

I'm not in mich of a typing mood, but the altitude you do the test at, how you do the test and what king of gauge you use can make a big difference (plenty about it on the Internet). The smaller the engine the more sensitive it would be to all these things I assume as well. Sounds like you should forget about the PSI for now (It did fire right?) and start looking at the carb if it has been sitting.

[tri again]

Where in Oregon?
Yeah, don't worry too much about posting.
Must of us check 'what's new' every day so you're getting full exposure for your questions even if you post in the new member area.

As far as compression, elcam said it.
Gauge type, hose or pipe diameter, throttle full open, altitude etc.
I'm such a freaking burnt geezer farmer I'll just check with my thumb, and see if a few drops of oil makes it better, if not, rings aren't worth doing.
If it smokes like a bbq but runs good, 99 cents valve seals might be the answer.

Welp? welcome back.
Hope you made it through the freeze ok.

[El Camexican]

If it smokes like a bbq but runs good, 99 cents valve seals might be the answer.

125 Tri-Moto is a 2 stroke (you Honda guys!);)

[airbats801]

I live in tigard, but do most of my riding behind scappoose

Yeah I was just looking for a average number.

I wanna take a look at the reeds on this things. It was weird it fired right up for a few secs, then I couldnt get it to fire again whatsoever. Plug was dry as well.

I'll pull the carb and reed cage off and go through them real nice. I may try one of those reed spacers, and toss in a set of boysen reeds.

I'm pretty damn excited about this 125. I'm already eyeballing a 175 jug, but I think for now the 125 should be enough.

[El Camexican]

It was weird it fired right up for a few secs, then I couldnt get it to fire again whatsoever. Plug was dry as well.

I'll pull the carb and reed cage off and go through them real nice. I may try one of those reed spacers, and toss in a set of boysen reeds.

Dry plug screams fuel issue. Make sure the pilot jet is clean, take it out to clean it but don't break anything doing it. Also makes sure your fuel is flowing from the tank. Boyesen reeds will make it run a little crisper down low, but don't waste your money on a carb spacer.

[airbats801]

you dont think the reed spacer will help with the low end?

[El Camexican]

you dont think the reed spacer will help with the low end?

Nope. If it did Yamaha would have lengthened the intake tract to start with. Save your cash to buy jets. Proper jetting will add way more power than $0.25 worth of alumiminum that you paid $20 bucks for. Make a note of the numbers on the jets when you take the carb apart so you know what to buy later.

[tri again]

125 Tri-Moto is a 2 stroke (you Honda guys!);)

oops. got sidetracked by the magic of the 110 stories and there's another thread about 110 vs 125m.
Just realized that if I truly knew what I was doing, I wouldn't come here every few days looking for answers.

Would oil in the cyl help with ring diagnosis like a 4 stroke?

[El Camexican]

oops. got sidetracked by the magic of the 110 stories and there's another thread about 110 vs 125m.
Just realized that if I truly knew what I was doing, I wouldn't come here every few days looking for answers.

Would oil in the cyl help with ring diagnosis like a 4 stroke?

Yea, oil still seals them up. Just kidding about the Honda thing, I have trouble telling a 90 from a Big Red! I learn tons on here:beer

[tri again]

Looks like me an airb were kicking around a few different trikes on a couple different threads.

I looked at a few big reds for sale and I get there and yes, they are big and red but said 90 on them

[Ghostv2]

If you had an account on here before and remember ANY of the information you used to create it, it can be recovered. Message an administrator and he will help.

[dislexicdime]

What up shaun ! If i remember right anything above 90 on a triz 125 should be enough compression to fire. It would he funny if there is something jammed in the reeds like the last 125

[Howdy]

If you had an account on here before and remember ANY of the information you used to create it, it can be recovered. Message an administrator and he will help.

Yup, we can search the accounts with proper info. ;)
Howdy

[barnett468]

I live in tigard, but do most of my riding behind scappooseinternet says scappoose is 62 ft above sea level.

you loose around 5 psi of compression for every 1000 ft increase in elevation above sea level.

all mfg's recommended comp ratings are for 0 elevation.

the link in the second post says 128 psi is stock, i could not find it in the manual but even if that is correct it is low and you will definitely benefit by having the head professionally machined and increase it to around 150.

of you replace rings you must have the bore accurately measured.

it should be measured around 1/2" from top, in the middle and 1/2" up from the bottom.

it also needs to be measured in 2 different positions at each elevation 90 degrees apart fro each other to check for out of round.

if it is more than approx .0015" out of round or has more than approx .0015" your rings might bot seal.

if the combination of out of round and taper is more than approx .002" your rings might not seal.

your piston should be measured 90 degrees from the pin just below the rings, half way between the bottom ring and approx 1/4" up from the bottom. if the center measurement is greater than the bottom i would replace it.

if the piston to cyl clearance is more than approx .004" i would bore it.

the spacer will lower the compression and soften the power band.





Yeah I was just looking for a average number. I think for now the 125 should be enough.even if your gauge reads high by 20 psi it still should at least run as mentioned by others.

even though your plug is dry i would still lay the plug on the head and look for spark.

will it still run with starting fluid?

if you are not getting fluid gas/oil on the plug it i would spray some type of oil in it like wd40 or 6 in 1 or pbs etc. it will lubricate the cyl and bearings.

kick it over a few times with the plug wire off to get it on the bearings.

it might start with 1 of these fluids, if not you can use starting fluid again.

use oil every time before starting fluid or you might kill your eng.