250r topend rebuild

[topdogjosh]

Just picked up my R yesterday and need a little help. I know that I will have to do a topend rebuild eventually, and I have a pretty good idea on what to do, but since this forum is all about the 250r could someone do a step by step on the topend rebuild. I mean every step, from taking off the gas tank(if thats actually required) to puting on the last bolt. This would be a great sticky, so come on guys and dont let me down.

[Aceman]

Don't let you down?? How about you don't let us down by trying to use this forum as a substitute for buying a manual with clear step-by-step directions. Then again, if you've read the manual and still have some questions, we're all ears.;) I'm not trying to be harsh, I'm just a firm believer in owning a manual for the quad you have.

[topdogjosh]

Well mr. harsh, sorry to let you down, but I do have a manual. These things read like stereo instructions. I read a post in the maint. forum on changing the rear axle bearings for a 400ex(used it to change the ones on my r today) that was very helpful and a lot easier to follow than the manual. In fact, if it is such a waste of your time, why'd you even post a reply in the first place. Anyone with anything useful to post? It would be appriciated.

[my88r]

Originally posted by topdogjosh
Well mr. harsh, sorry to let you down, but I do have a manual. These things read like stereo instructions. I read a post in the maint. forum on changing the rear axle bearings for a 400ex(used it to change the ones on my r today) that was very helpful and a lot easier to follow than the manual. In fact, if it is such a waste of your time, why'd you even post a reply in the first place. Anyone with anything useful to post? It would be appriciated.

well Aceman is right. if a manuel is so difficult for you then i would take your motor to a engine bulider. for me the honda service manuel is very understandable. i own 2 the honda and the clymer. you should respect the knowledge you get out of this site.

[86 Quad R]

i'm not going to explain blow by blow how to do the top end but if you'll read THIS (http://www.duncanracing.com/techfaq/Tech_2-stroke-top-end-assembly.phtml) tech info in conjunction with the service manual you should be able to wade through the process just fine.

as mentioned, if you do hit stumbling blocks we'll be able to help ya out but we cant build it for you(so to speak) :blah:

[Aceman]

My88r, I wouldn't go that far, I'm still learning myself.:p

Topdog, I never said it was a waste of my time. I just don't understand why some people can't figure some things out on their own, a little problem solving never hurt anyone. I have a clymer manual myself and don't have any problem following the steps when needed.:confused:

[250r4life]

that clymer manuel is great... i've gone through my whole entire engine with that... very easy to understand...

i agree- if you have the clymer and are still having problems- take it to a shop!

[250r4life]

its called reading, top to bottom, left to right, group words together as a sentence, take tylenol for any headaches, midol for any cramps :D

[my88r]

Originally posted by 250r4life
that clymer manuel is great... i've gone through my whole entire engine with that... very easy to understand...

i agree- if you have the clymer and are still having problems- take it to a shop!

yea if you cant understand the clymer than take it to a shop.period

[topdogjosh]

I havent even tried it yet. The bike runs fine right now. I just thought it would make a good thread, for myself and others who have never done it. Im sure I can do it with no problems, just thought you experienced guys might want to throw us a bone. But, if it really is too much trouble, just dont post anything and let the thread go to the bottom of the list.

[topdogjosh]

I havent even tried it yet. The bike runs fine right now. I just thought it would make a good thread, for myself and others who have never done it. Im sure I can do it with no problems, just thought you experienced guys might want to throw us a bone. But, if it really is too much trouble, just dont post anything and let the thread go to the bottom of the list.

[my88r]

Originally posted by topdogjosh
I havent even tried it yet. The bike runs fine right now. I just thought it would make a good thread, for myself and others who have never done it. Im sure I can do it with no problems, just thought you experienced guys might want to throw us a bone. But, if it really is too much trouble, just dont post anything and let the thread go to the bottom of the list.

:rolleyes:

[beobe99]

doing a top end isnt hard at all. ONLY real thing you need is a tourqe wrench for the re-assembly.

Deff take your tank off just because it will give you more room basicly and make life easier, I would even take the carb boot off for more clearance after taking off the carb itself, take your exhuast off of course and gather the right wrenches for the rest, pull your spark plug, unbolt the head, unbolt the cylinder and gently slide it off the piston... Once you have it off check the cylinder for score marks, scratches, pitting whatever.. it should be nice and smooth to the touch. Even if it all looks good you should, or at least I would take it to get honed out (or bored of course if needed) have the tech let you know what size piston to order and of course buy a piston KIT with rings, clip, bearng and top end gasket kit. (Im not sure what bore the stock gaskets are good for so thats a deff. Qs to ask)..

Putting it back together is cake work compaired to a 4stroke. Just make sure you follow the tourqe specs and you dont scratch the shiz out of anything when putting the rings on (there is a ring seperator for putting the rings on but I always got away with doing it by hand.

Ok so i tried to explain it all hehe! but what was said above by 88r and ace is what you should do. just grab a highlighter and highlight the steps youve completed to make it seem less complicated. Once youve done this once youll be shocked that you ever thought it was hard or complicated trust me.

hope I helped

[beobe99]

Almost forgot.. when you pull the cylinder off be sure to check your rod.. it will have some play side to side but should NOT have a up/down play to it... If it does your rod bearing will prob need to be replaced and doing that cant be explained on here or in person and you WILL only have the manual to rely on or a shop.



Originally posted by beobe99
doing a top end isnt hard at all. ONLY real thing you need is a tourqe wrench for the re-assembly.

Deff take your tank off just because it will give you more room basicly and make life easier, I would even take the carb boot off for more clearance after taking off the carb itself, take your exhuast off of course and gather the right wrenches for the rest, pull your spark plug, unbolt the head, unbolt the cylinder and gently slide it off the piston... Once you have it off check the cylinder for score marks, scratches, pitting whatever.. it should be nice and smooth to the touch. Even if it all looks good you should, or at least I would take it to get honed out (or bored of course if needed) have the tech let you know what size piston to order and of course buy a piston KIT with rings, clip, bearng and top end gasket kit. (Im not sure what bore the stock gaskets are good for so thats a deff. Qs to ask)..

Putting it back together is cake work compaired to a 4stroke. Just make sure you follow the tourqe specs and you dont scratch the shiz out of anything when putting the rings on (there is a ring seperator for putting the rings on but I always got away with doing it by hand.

Ok so i tried to explain it all hehe! but what was said above by 88r and ace is what you should do. just grab a highlighter and highlight the steps youve completed to make it seem less complicated. Once youve done this once youll be shocked that you ever thought it was hard or complicated trust me.

hope I helped

[wilkin250r]

Here is the problem with "step-by-step" instructions. Either we make is so complete that it becomes even more complicated than the manual, or we make it so simple that people (like you) figure that you don't need to do any of the other stuff.

For example, your connecting rod and crank might be just fine, but how do we know? Do we include instructions to check that?

Do we include instructions to check your head and base bolts to make sure they are secure and not stripping out?

Do you need a step-by-step to adjust the ring gap, or is that something you can figure out yourself? What if your ring gaps are just fine from the factory, do we even NEED to put it in?

Are you checking your own piston/cylinder clearances?

Are you using a spacer plate? Do we need to include instructions on how to add one?




Cripes, you want detail, I can write a set of instructions that will give you a brain aneurysm. You'll be wondering why the manual uses 10 pages, but my instructions took 27 pages.

[topdogjosh]

Thanks for the help. I know you guys have done this many times so your advice is a definite plus. Heres a pic of my new bike.

[topdogjosh]

another, I plan on riding it for the rest of the summer then tearing it down this winter

[topdogjosh]

its got boysten rad valve, 38mm carb., FMF pipe and silencer, and a prodesign cool head.