1985 250R Engine Rebuild~~~HELP!!~~~ Now W/Pics

[big schott]

OK so I have been around 4 stroke 3 wheelers now for sum 30 years now and I have to admit I havn't had to do much in the "Rebuild" part. So I bought a 85 250R this past summer and now it's rebuild time. I didn't plan on doing a day-by-day report on this build but I do need HELP!!

The guy I bought it from told me that it had never been overhauled and after taking off the head found that this might be correct! The jug is woar oblong , yes it looks like it is egg shape and when you look down inside the sides of the piston are tight and the front to back you can see the rings of the piston touch the sides of the jug !! I'll get the pics of this when I get them off my phone.

So 1st question. Can I have this bored? To what? , Can I/ should I replace the Sleve? If so How do I get it out. (I have a good metal press)

Also I took off the RH side cover and took a look at the clutch and noticed that the last person in their did some "Clutch work". When he put the front plate on he twisted off one of the five studs and now it only has 4 bolts and springs holding the clutch together. Now I know I need to fix this but I need a replacement "CENTER, CLUTCH" Bike Bandit Part #65653-001 but don't want to pay $64.09 for a new piece.

So Question #2. Does any body have this part sitting around or maybe a whole different clutch basket?

Thanks People I know you will come through on this!

[oscarmayer]

if it's that bad, your probebly going to have to get a new jug. that's not common to go that long. so sorry but your got issues and a $ pit. the good news is there's a ton of parts. also some (not sure about the 250r) motors have a sleeve you can press oput and replace with a new one.

[brapp]

take your jug to a good machine shop you trust and have them mic it and se ehow far oblonged it is you may be able to clean it up and get it bored out to a fresh bore. and as far as the clutch inner hub goes. just be glad its not oen fo the discontinued parts and ponny up and just bu the part new youll be glad you did ther eis nothgin liek new parts compared to 20 year old parts!

[RoscoW]

Take the cylinder to your local machine shop and have him mic it as per the service manual (multiple locations in the bore). He will be able to tell you what bore size will clean up the cylinder. Buy the piston and have him bore and clearance to the new piston (to avoid issues)
I don't think you would need to sleve it if it was on it's original bore.
You can find the clutch inner hub on E-bay all the time or try service honda for new.

Ross..

[big schott]

Hey thanks for all the advise. I have checked on ebay and found a complete rebuild kit (piston,pin,gaskets,sleve) all for $225. Now I know the piston is a Wiseco and Honda is better but, If I don't plan on running it hard or racing would this be OK?
Also I have been finding the clutch part on a few spots and each time I find it it gets cheaper So I'll just looking this week.


One more question... does the sleave need to be recoated with some kind of nickel after the boring?

[blasterman88]

I have never seen a cylinder wore so bad it was junk. The stock honda sleeve is pretty thick. You should be able to just have it bored...You do not need to re nikisil the bore as it is a cast iron sleeve....I would definetly buy an oem clutch hub...with only 4 springs you will not have the proper force to keep the clutch from slipping..

[motoman110]

Wiseco makes 2 mil over bore pistons that work with stock sleeves, Im sure if that sucker is still on the stock bore it will have enough meat to work with. I picked up my hole top end kit for my R from wisesco for $150 and that was for the 1.5 mil over piston kit. caculated it out and its 270 now, with one bore size still left

[DeePa]

yeah, your cylinder will be fine...oscar you never cease to amaze me with your comments....

stay away from bikebandit.

go to servicehonda.com they have the new style microfiches with easy ordering now, unlike the old process...youll save 15-20 on that clutch part.

I would split the cases and do the crank bearings, as well as all new seals. You should do all of the bearings, especially the countershaft and mainshaft ones. Its all up to you...

[oscarmayer]

edited:

I talked to deepa in pm and he does have a good point, before i go talking about replace it, it is a good idea to get it checked over. what looks to be like major damage to someone whom is not that familuar with the 2-cycle stuff, could be minor but just looks bad. Thanks for the correct deepa. your a good man. hope you guys can oversee my ignorance and gun jumping.

[big schott]

OK so, you have to get a load of this.....!!!
I had the jug taken to Smokies machine shop in Fergus Falls,Mn and he took one look at it and said thats not the correct piston for that machine. After looking at the situation he also said the jug had been bored 10 thousandths at one time and then the wrong size piston was put in (too small for the bore). That is what made the piston wear the jug oblong.
here are a couple pics. Sorry about the quality, I only had my cell phone.

Enjoy
[IMG][/IMG]
[IMG][/IMG]
I do know when it ran it rattled and I thought it was the crank bearing but I stand corrected. He also showed where the piston had 3 cracks in it on the sides, right around the area where the pin holds the piston in place. A little more running and the piston would have let go..

BANG!!!!! What the @#$^%@@#@!!! At least that is what I would have said.
I am getting it bored and he will get me the correct one that will last another 20years.

[blasterman88]

it prolly wasnt the wrong size piston, but just had too tigght of a clearence....wasnt honed properly

[Micahdogg]

Keep in mind when retorking those clutch springs, the bolts will bottom out in the stud...so they take almost NO torque. Just snug em up. Maybe a lil extra grunt, but no big torque.

As for nickle coating on the cylinder....I don't know if the 250R cylinder is nickel coated or not? I think not, but I'm new to these. Anyway, I would consider it as you can do hones yourself. If you get the right ball hone, you can't wear through the coating so no worries about screwing up the hone. And you probably wouldn't have to replace a piston again...just keep tossing new rings into it.