Hello-
I recently picked up a 1987 lt80 for my daughter. I paid $100 bucks for it and it ran. Just this last weekend, I decided to do a compression test on it to because it would only start with ether. Compression was approx 87psi! Bummer, time to rebuild the top end. This started the ball rolling! I now have the head and cylinder pulled to be re-bored for a new piston and rings. I am having the head shaved down .030 to boost up the compression a little at the same time as the cylinder is being rebored.

I then decided to break into the clutches as it appeared ZERO maintenance was done on this little ride. Much to my surprise inside of the case looks real clean. I still want to pull the clutches, but am having a bear of a time getting the nuts off. ( I know there is a joke in there somewhere!) I have the factory manual that I downloaded, and it calls for a special tool to hold everything in place so a socket can be used. Is there any other way to get these front and rear clutches apart? Sorry for being so long winded! It is amazing how this little quad has taken on a life of its' own.... Thanks so much for your time and help.

 

Welcome to the forums.
Most use a impact wrench to get the nuts off.

 

I will give that a try this morning! Thank you. Is there anything special (as far as wear is concerned ) I should be looking for while they are apart? I think I am going to lighten the clutch arms while I am at it and remove a couple of the rollers. I have seen some articles addressing this, so I won't beat a dead dog. My question is the springs- should I replace those while I am at it?

On another note, I plan on rebuilding the carb. I just picked up a trinity exhaust. Should I re-jet the carb to match the new exhaust? I have read somewhere that this should be done. What size jet? I will have a shaved head and slightly oversize piston as well. With these upgrades, I want to make sure everything will work together once it is put back together.Thanks again for your time.

 

Look for worn/flat rollers. If they get bad enough, they can gouge the tracts on the variator and roller plate.
Check the rear clutch bearings. I get alot of those bad.
The stock springs are fine.
I'd leave the stock jetting in and keep an eye on the plug color.
The had mod will help the comp but the oversize piston means nothing for power.
Your on the right track.

 

Thank you! I just got the bench cleaned up and the tools organized. I am going to give it a whirl on pulling the clutch covers. I will let you know what I find out.

 

So the back clutch pack is now pulled. It appears that someone broke a corner off of each shoe. Looks like a set of pliers was used. I am making this assumption as there were no bits and pieces that fell out when I pulled the side case and no visible debris came out when I pulled the cluster apart. What the HECK? I guess I will be ordering a new clutch pack before I cut them down and drill them. Can you purchase already lightened clutches?
The inside of the clutch housing is a bit scored, not terrible, but it is definitelly there. Can these be turned, honed or just replaced?


I now have the front pulled as well. It just took a little effort. The front does not look like it ever was apart. There are some flat spots on the rollers, the moveable drive face plate has some wear on each tab associated with the flat spots on the rollers. The inside of the moveable drive face also has wear. There was so much grease and nastiness in there, none of the rollers could move. Kinda explains the flat spots I guess. Do I have to replace the whole set-up? I understand the red rollers are more durable than the white. Are these available? I don't want to put this back together with sub-par parts that will cause future issues, but I also don't want to spend where I don't have to. Thanks in advance.

Thanks

 

I'm thinking someone may have tried to lighten the rear shoes and it just looks bad?
It shouldn't hurt. (I read it as the shoe not the pad).
If the scoring is terrible you can get a new drum. I don't turn them down.
You'll need a new variator, roller plate and rollers. Sorry, haven't seen new red rollers in 20 years.

 

Thanks. The shoes were butchered, but probably still usable, but after further examination, the pads were almost non-existant. Can you buy just the shoes and pads, instead of the whole clutch assembly? I have not seen just the shoes listed.

I got the reed assembly apart and then metal reed looks great. I already ordered the Boyesen reed so, I guess I will have an extra.

One more question, sorry for asking so many. I have read the sprockets on the 87 were different from later years. Do I need to change the gearing? I am looking to running this in the sand some. Any suggestions.

The frame is now completely disassembled. I am going to have it and the wheels sand blasted and then I will repaint. So much for my $100 deal! It has been fun though learning a new thing. It amazes me how neglected this little ride was and that it still ran and drove! It should be leaps and bounds from what it was if I put it back together correctly.

 

You have to buy the rear clutch shoe assembly.
I'd install the Boyesen reed. It's a 2 stage type.
The 87/88 gearing is 428 size chain/sprockets (12/26 gearing). The chains came loose a lil too much so they went to the current 520 size chain/sprockets (10/22 gearing). It seems the 520 won't jump off as much.
I use the 428 sprockets and use #40 chain. The machine rolls very easy.
I'd stick with stock gearing. You can go up a tooth on the front if need be.
Ask anytime.

 

Well I started cleaning up the frame. I fabricated some brackets so I now have the stock front bumper from my KFX 400. The bumper on the Lt80 was bent and was going to need work anyway, so I figured what the heck. It looks pretty good. Can't wait to get this thing painted and put the top end and clutch assemblies back in it!

LT80- I sent you a PM and email regarding parts. Thanks