1986 trx200sx rebuild

[honda_atc200es]

ok, lately alot of things have been piling up on the "wtf is wrong" list. and since the quad thread doesn't get many posts i feel the open forum would be easier to discuss this, and it should fit because what is wrong with my bike is applicable to anything with an engine.

first on the list: black soot on the plug, i can only assume this is a rich mixture, but it isn't wet, just dry carbon deposit, i have tried everything but a carb rebuild and new jets to fix this, but something tells me there may be other factors that are contributing to this. one thing i found out is that the air mixture screw is missing, but here is what is weird, that would make it lean would it not? there is also no air filter, no airbox lid and the exhaust has a hole in it. i don't think this is a float issue because there haven't been any instances of the bike leaking, unless i leave the gas on for over 2 days.

second: the turning radius is horrible, if you apply any throttle at low speed u cant turn, now yes it is a quad, but nothing turns this badly. one tie-rod is loose, but i don't think that is the problem. what i think is, is that the left rim is bent (not the brake assembly, just the rim itself, but would that cause this issue at low speed?

third on the list, when moving the bike there are periods of tightening and loosening of the chain, making squeaking noises and intermittently increasing the force needed to push the quad manually, if something is bent how could i determine this?

fourth: today i was taking the plastics and tank off to clean the carb (with no air filter i do this after every ride) and the two right bolts on the head of the engine (if sitting on the bike facing forward) were not tightened at all. i took the bolts out, and the bottom threads are destroyed, like they shredded or blew apart. this appears to have been recent, because where the bolts were screwed in is nice and clean like its never been exposed before.

any ideas? im trying to make a definite list of what i will need so that what ever syko dosent have i can save up the money for the remainder

[300rman]

the chain going tight-loose is most likely a worn chain. replace it.

a loose tie rod could very easily affect the turning radius as you describe,.
unless the wheel is SEVERLY bent, it souldnt have that much effect at low speed.
but, if the bike hasnt always done this, there is a good possibility something else is bent too. but yes, quads turning radius can suck sometimes.


If you are running your bike with no air filter, you are a moron. the dirt doesnt hurt the carb so much as it gets sucked into the engine and destroys the top end.
if you were referring to the air box lid being off, you still shouldnt need to clean the carb after every ride.......just check the air filter and service when necessary.

if in fact you have taken the carb apart so many times, something may be damaged by now, and causing it to run rich.
the air screw is different on certain carbs. some will richen up and some will lean out without one.
but, carbon deposits could also mean the bike is burning oil.....which comes from running the bike with no air filter.


when you say the head bolts, you are referring to the bolts that hold the head on the jug, correct? if those are messed up, you need to get that fixed or you could blow a head gasket and become stranded.

[honda_atc200es]

the chain going tight-loose is most likely a worn chain. replace it.

a loose tie rod could very easily affect the turning radius as you describe,.
unless the wheel is SEVERLY bent, it souldnt have that much effect at low speed.
but, if the bike hasnt always done this, there is a good possibility something else is bent too. but yes, quads turning radius can suck sometimes.


If you are running your bike with no air filter, you are a moron. the dirt doesnt hurt the carb so much as it gets sucked into the engine and destroys the top end.
if you were referring to the air box lid being off, you still shouldnt need to clean the carb after every ride.......just check the air filter and service when necessary.

if in fact you have taken the carb apart so many times, something may be damaged by now, and causing it to run rich.
the air screw is different on certain carbs. some will richen up and some will lean out without one.
but, carbon deposits could also mean the bike is burning oil.....which comes from running the bike with no air filter.


when you say the head bolts, you are referring to the bolts that hold the head on the jug, correct? if those are messed up, you need to get that fixed or you could blow a head gasket and become stranded.

the wheel is severely bent, so that is most likely my issue there

i am a moron hehe, the bike never had a filter since i got it, but it was my brothers quad before it was mine, so he never maintained it, im looking at putting 300 dollars into it, including a brand new topend.

as for the bolts, its the 2 on the right side, and what is weird is that the head overlaps the jug, is this normal? ill have to get pictures tomorrow. hopefully after i get my parts though im just taking this engine out and keeping it for spare

here are some pictures

http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/DSC01810.jpg

http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/DSC01818.jpg

http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/DSC01821.jpg

[honda_atc200es]

bumpity bump

[SWIGIN]

set your front end to have 3/8'' toe in and try to get some camber too.

[honda_atc200es]

what do you mean swingin?

[SWIGIN]

toe in is just like it sounds.......point your toes in towards each other wile standing

now ajust your tie rods to point the tires in towards each other 3/8''

hears a pic of me in air......you can realy see the toe in but you only want around 3/8'' with the quad on the ground

camber is the way the tires tilt .....i like the top of the tires tilting in 1 1/2''.....you never want them tilting out the other way

[honda_atc200es]

yeaa, i hear what your saying, i know about the toe in, but what would it accomplish ;),

well actually i see where your coming from as far as if it was my suspension that is outa wack, but i found out the rim is bent, i made sure by swapping the rim to the other side

[SWIGIN]

um..........its not a bent wheel

to turn tight set it like i said and be amazed....lol

[SWIGIN]

here's a better pic of too much of a good thing

[honda_atc200es]

that may help turning radius, but what i mean is, my wheel wobbles, about 2 inches left and right, its highly noticeable even in first gear

[ironchop]

I agree with SWIGIN....it`s alot like having yer car alignment done....when the camber/castor is incorrect, the tires will cause enough friction to work against the steering dramatically and also prematurely and unevenly wear out the tires and cause oversteer or understeer conditions which are both hard on the equipment and potentially VERY dangerous to the rider in an adverse terrain situation.

that bent wheel would be a good indication that you have a bent A arm or tie rod as well...a wheel taking a hit hard enough to be "severely bent" is a hit hard enough to tweak the whole damn frontend or at least everything connected to that wheel

black plugs can also mean yer rings or valve guides are starting to let some oil past and are burning on the plug....when my plugs start lookin sooty when my carb mix is set correctly, I know the rings or valve guides need a look-see

is the cap for the cam journal missing, been removed on purpose or is it part of the valve cover assembly?...any bolts holding those caps or the head to the jug need to be torqued correctly but the threads need carefully chased with a tap BEFORE you reassemble...one little aluminum thred chip leftover in the holewhen you scre the bolt back in and BADOW!....the rest of the threads get destroyed and sometimes it "locks" the bolt in the hole and snaps off clean when you try and get it out....I`ve had front axles do exactly that


"im looking at putting 300 dollars into it, including a brand new topend.".....I think I can safely say you should bump that estimate to about $500

you say you rebuilt the carb with new jetting and whatno but all that has no effect whatsoever if the airscrew is missing, the box cover is missing, and there is no airfilter present.....you MUST have the proper pressures created by all those variables in order to properly setup the carb or you are wasting time and money...and this includes the hole in the pipe you mentioned....that affects carb jetting also...maybe not bad enought to prevent riding but enough to make a good running machine struggle to breathe right

as for the chain tightening and loosening....if you mean the chain links themselves bind up and wont rotate, the chain is Fu%#$....you can try and lube it but chances are the damage is already done...I prefer sealed O ring chains myself
one other possibility I have encountered was that my axle was so bent from a monster jump/crash, that the end was turning way out of round so badly that the sprocket would have almost an 1 13/4" of runout in a single revolution causing the chain to tighten then slacken again and so on....throw it up on a milkcrate and rotate the axle checkin for runout


steering under acceleration is a tricky issue....are your front tires good?....I know guys who destroy knobbies riding on the road and then complain that their machines push steer under throttle...a good directional tread pattern running parrellel with the wheel rotation seems to work wonders for reducing push steer....square knobbies or chevron style treads allow the tires to slide laterally the same direction as the tread under steer....that`s why sand tires have one straight rib down the middle as do smaller farm tractors....reduces push steer


first thing I would do is check WHOLE chassis for bent stuff...some models can tumble down a mountain and ride off unscathed and some can hit a chuckhole and turn into a horseshoe on wheels....bent chassis makes all the mortor in the world worthless

second, replace missing air screw, airfilter (I suggest a UNI properly oiled), and the airbox cover...and fix the hole in the pipe....THEN remove what you rebuilt on the carb and set it up all over again...with a box of brand new plugs for testing sitting nearby....just the lack of the airfilter lets tiny dust ,grime, and sand which basically sandblast yer rings,jugs, and valve seats and guides costing $$$ to remedy

third,get those threads chased out and blown out REAL good on that head....use new bolts and torque them correctly....then set your valve clearances

if that doesn`t clean up the sooty plug after properly setting air/fuel mix, remove the head and check rings and valve guides/seals and replace if needed


then relube and grease all rotating parts and friction areas, change the oil/filter, check all axle and wheel bearings and replace that loose tie-rod end

sounds like a HELLA bunch of work and it IS....but since most guys don`t maintian their machines very well the broken part tally and $$ invested to keep it riding can run up VERY quick...and yer machine NEVER breaks down in front of the garage in yer driveway....it breaks down 3 miles into the woods on a weekend you been planning with yer buddies for three months and NOBODY has a tow rope to pull you out....which bums out everybody`s good time....that`s Murphy`s Law of ATV maintenance

[honda_atc200es]

i really appreciate the response =] i will try all those things.

to answer some questions, im getting the parts from syko for 300 bucks, a brand new freshly bored top end and piston, and the bottom end off his trx as well, i might just take the entire engine out of my trx and keep it for a spare.

as for the jetting, the bike will not run with the lid on, what so ever. i also have to adjust the throttle cable as a sort of choke when i warm the bike up, i cant use the standard choke because the bike will stall out, i cant figure why its not getting enough air.

the chassis itself i dont belive is bent, i see no issues other than the rim, i have taken just the rim off and put it to the other side and it then wobbles on that side, the push steer is most likely due to bad tires like you said, i have been road riding for 2 years.

alot of the things you mentioned i have been planning on doing, so im glad to know i had the right idea, and now i have a check list to keep busy. i know this wont be no 2006 400ex, but im not buying a new quad for a very long time, so i like to make this one decent :)

[RedRider_AK]

If your wheel wobbles, your bearings on the spindle could be blown out. Set the quad on a crate so the front wheel is off the ground and try to move it up, down, left right, check it for play.

[honda_atc200es]

what i id was (since i couldnt find my jack) put my bmx ramp against a wall, drove the quad up, chalked it, one wheel was hanging off, which happened to be the bent rim, i took it off, leaving the hub, and switched it to the other side, now the right side had the wobble, making it obvious the rim was bent, its hard to explain, ill try to get a vid to show just how bent it is, but it dosent seem like anything else is bent. i am replacing tie rods, there is a little play in one side.

[YTZ Money Pit]

you're chain problem could be the swing arm bearings. the bearings on my buddies quad had too much play and did what yours is doing because the rear end was moving

[honda_atc200es]

hmm, makes sense, ill check that this afternoon thanks =]

[honda_atc200es]

how do i go about adjusting the valves on an 87 engine? got the head back on, (held on with only 3 bolts), and now it wont start, it sputters once but wont start. i tried messing with the valves a little but i didnt notice a difference, but it has plenty of compression

[honda_atc200es]

wow i feel dumb.... it wasnt the valves at all, i forgot i plugged the intake... talk about something obviouss haha

[honda_atc200es]

ok, bike is now completely stripped down, waiting for some new(ish) parts =] i was an idiot and didn't organize the bolts though, so that will be an issue. does anyone know if its possible to buy a complete bolt set? or find a list of the bolts i need? also is the wiring diagram for the 86-87 200x the same as the trx? it looks very similar to the wiring harness i have, so i dont see why it wouldn't work. also where could i fnd a good checklist for putting the top end together? not so much on like how, but more like what i have to make sure of so i dont ruin anything. sorry for all the questions, especially about a quad (i need a trike again =[ )

some pics- http://s199.photobucket.com/albums/aa213/foxstang89/trx200sx/

http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/DSC00028.jpg
http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/DSC00033.jpg
http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/DSC00035.jpg

[honda_atc200es]

got mah parts! (thanks syko!!:beer ) i cant wait to get to work on this sucker, im already discussing with a friend about powdercoat and plastic paint around january, it looks like this will be pretty much a fell rebuild. now all i need to get to work on the engine is a torque wrench and a service manual, then it will be time for new tires/rims, then exhuast, finally paint/powdercoat and i guarentee this will be the nicest trx around. i figure by the end of summer 09 ill sell it and buy a trike =]

http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/1110081509b.jpg

http://i199.photobucket.com/albums/aa213/foxstang89/trx200sx/1110081627a.jpg

[honda_atc200es]

ok, so i got very side tracked today and decided i would take apart the 87 engine so i could have a general idea of what to do when the bottom end gets here, and stupid me, i pull the recoil starter without having tension on the chain, and it wrapped around the sprocket.

i had to take off the right side case to un-do it, and now im stuck, how do i put it all back together the right way? i cant find any detailed diagrams and i dont have a service manual yet.

i may just plug it all up and place it to the side till i do get a manual and then sell the engine after its put together. i was pleased to find that the engine was in great condition, a little bit of carbon build up, but with how rich this bike was running im not surprised.

[honda_atc200es]

Its all done, i started in November, finished in march, in time for spring riding =] I fixed every major issues besides the following

-few bent sprocket teeth
-electric start one way clutch is bad
-front brakes dont work (even after new pads and new fluid, bled brakes)
-bent front rim
-slightly rich
-seat needs to be reupholstered

Here are some pictures

or not, ill upload them tomorrow