So I picked this toy up about a month ago 2001 lt80 and have been making some updates for us adults to play around on. I've removed the oil injection, port matched the cylinder and cleaned up the casting transfer ports, honed, and milled the head .04, boysen reeds, lt160 front shocks (still need to figure out what is a cheap shock for the rear for 105lb-185lb rider, any ideas?), midwest mini handle bars which are great!!!, their gear plus tensioner kit, dropped the needle and threw a 90 main in it. I'm still not where I was hoping to be so i figured I'd look at the clutches as there is a bunch of info on it. I'm looking for alot of low end power!!!! lol

So I looked at the rollers and they all have a small flat spot on them and of course I hear they need to be replaced but it is maybe 1/8 wide and you can barely feel it with your finger. So those have replaced them is this when you should do it? If so did you find that it made a huge difference or were your rollers really shot?

Needless to say I removed 2 rollers anyhow just to try it out and she was alot more peppy down low but not shifting out in the rear it seemed so am I right to knock that down to 180grams and that will allow it to up shift it faster? I saw this on ebay today so I picked up a stronger rear spring just to play around with......it might have been a waste of money....any thoughts? http://cgi.ebay.com/ebaymotors...em=&item=180294660494

I'm very familiar with setting up clutching on snowmobiles and typically I would clutch it to hold a particular rpm just past the peak horse power then when I would bog it down (wet snow) it would be pulled into the peak of the power band. As the clutches shift out all the way if there is not too much drag the rpm would gradually increase past the powerband to get you to max speed. granted there is alot more to it but I'm trying to do this same thing to the lt80.

With these small mods does anyone have any idea at what rpm I want to hold under acceleration? as there is little drag on top it'll probably rev out pretty good unless I was in deep sand which I compare that to riding a snowmobile in deep wet snow so I'd want to hold a certain rpm. I appreciate everyones help!!!!!

 

The flat spots on the rollers are huge, we've lost races because of small flat spots. The problem is they just can roll in the variator and can actually hang up, the problem we were having until I took my smart pill is when Cole would slow quickly for a corner or whoops it would actually kill it because it couldn't back shift correctly. As far as the variator weights, the heavier they are the faster it will shift. I played with 6 different roller weights and ended up back almost to the stock weights. I have done about what you have done to the motor with the stock exhaust and carb (because of the stock limited rules) and the only thing that I found real benificial is the small springs. I put purple in it and I beleve I went to a 1250 main spring. If it is anything like ours anything over this really hurt us, it just couldn't get the rpms to make everything shift fully. Now if you put a different carb, air cleaner, and pipe on it so it gets rid of the choke points and can run high rpms then you will be able to benifit from the heavy springs in the rear and lighter weights in the variator. It is similar to a snowmobile but almost in reverse manner. I did a lot of work on the snowmobile clutches and they were easy to figure out, these little buggers will make you pull your hair out until you find the right combination.

 

EWelcome to the forums.[img]i/expressions/face-icon-small-smile.gif[/img]
Well,, yes the spring was a mistake,
#1) It's right hand wound spring. The LT80 is left hand wound. It'll unwind.
#2) Your motor is not making enough torque to get it to work. Install it and there will be no shifting of the rear clutch. Your problem with lack of down shifting is the rear torque spring but the 2000 spring is way too stiff. The stock spring gets hot and looses it's strength.
Flat rollers are a problem. More often clutch maint will help.
The pipe (you didn't mention which pipe you had) may get you a few more rpm's. The carb will not help. I can get 12k rpm's out of a stock carb and the stock filter works well.
Taking the rear clutch shoes down to 180 grams each will get rid of the low end bog on take off and is a good idea for a beginner mod.
The stock rpm is 6500. If your hitting 7000 I'd be greatly surprised.
Your low end problem is fixxed by getting rpm's up and clutch tuning to the power. Untill porting is done your going to get little accomplished.
Clutch mods (other than the rear shoe weight) does not work with a stock motor.
Stock HP is 5-6 hp.

How about a nice 14hp motor that turns 12k+? It's what your wanting.[img]i/expressions/face-icon-small-happy.gif[/img]

 

Thankyou for the feed back!!! I forgot to mention that this still does have the fatory exhaust on it and I have cleaned the oem filter which turned out
to be pretty bad.

I'm going to go ahead and order the rollers and a new rear spring to eliminate the posibility that it is bad. I'm really looking forward to the updates!!!
Now hotblooded what are these purple springs? The ones that are holding shoes I'm assuming and the larger main spring was needed also? LT80 do
you have any thoughts here?

Would it be a safe bet to get the new rollers and remove two of them (I'll eventually drill out all six to have to have the same over all weight of two missing
rollers) and then lighten the shoes to 180grams? I've looked at various threads and it looks like 3 holes are drilled to accomplish this on each shoe?? Any
special tricks here for us heavier rides (adults lol!!) I haven't split the shoes yet. My gram scale I ordered last night.

I think I'm going to get another set of rings for it too. When I picked it up it still had the oil injection (soming really bad) on and the top of the piston was caked with carbon deposits
and the sides of the piston had a dark haze to them where it appeared to has some blow by all though it was reading approx 153lb compression cold (snap on gauge) with throttle opened WITHOUT me milling the head .07 measured squish. When I did the port matching I was shocked on how much carbon deposits there were in the exhaust port, there was quite a build up. With the exhaust port there was a decent amount of the sleeve that had to be grinded out to match the port.....just a little
surprised.

Lt80 thankyou for your help I would love to have you build an absolute screamer but I'm kinda on a buget so I'm trying to get the most out of the motor/clutches I can do myself. I
know it will be a little more challenging to get it all dialed in right but I have to imagine there are few things I can do to get her running pretty good with all of this
great input from everyone. Thanks again!!!!

I want to keep this thread going as hopefully it'll help out alot of us!!

 

well I had two of them. 1 stock and 1 moored. for bigger people as im 300lbs I would suggest
1. mill the head
2. leave all 6 rollers in the primary
3. cut rear shoes to 180
4. remove oil inj.
5. run the he!! out of it!!!!!!
when you get tired of it send it the MR.LT80. and hold on. with both of mine in a drag. my moored lt80 with me and my 40lbs son on it =340 lbs and my stocker with the stuff done that I said up top with my 160 lbs buddie on in a drag race we were dead even till 25 feet then I pulled out to way to far for him to catch me. it also beat my wifes falcon 250

 

<div class="FTQUOTE"><begin quote>Originally posted by: onebigzj

well I had two of them. 1 stock and 1 moored. for bigger people as im 300lbs I would suggest

1. mill the head

2. leave all 6 rollers in the primary

3. cut rear shoes to 180

4. remove oil inj.

5. run the he!! out of it!!!!!!

when you get tired of it send it the MR.LT80. and hold on. with both of mine in a drag. my moored lt80 with me and my 40lbs son on it =340 lbs and my stocker with the stuff done that I said up top with my 160 lbs buddie on in a drag race we were dead even till 25 feet then I pulled out to way to far for him to catch me. it also beat my wifes falcon 250</end quote></div>

when you say 6 rollers are they lightened or oem? I though I read about some people not using grease on the rollers or do they need it? is white lithium ok or more of a bearing grease? I'm kinda for a loss why the rollers get flat spots in them. It looked like one side had alot of grease on it and everywhere else as clean as a wistle. I realize that centrifical force will push the grease to one side but with these clutches to get more of an even wear it seems either no grease or a dry graphite would be the ticket. Comet clutches used to make this that I used to use. By not having this grease on the rollers they would be free to perhaps spin a little no allowing for the flat spots to start as the rollers get stuck a little with all of that grease. What do you guys think?
Maybe those 3 plastic sliders on the moving plate require the grease. I don't have in front of me so I'm going from my not so good memory.lol

 

all oem on the rollers. take the weight off the rear clutch. having to little weight in the front gave me nothing but problems. not enough pressure against the belt. made it slip. lots of rpm no go. I use no grease. the reason you got flat spots on the rollers could of happened several ways. rollers could of fliped inside clutch, no clutch maint. , other parts worn out in clutch. check for groves in all clutch parts and replace parts if bad.
hope it helps

 

The purple springs that I refered to were the ones holding the shoes. I am not sure but from what I am hearing the lt80 may be some different from what the Eton is. One other thing you could check for is a Hetrik variator, they have them ground so the weights will roll a little further up. I am sure there are other companies that offer these but this was the only one my supplier had. I want to say it was 100 bucks or so with new weights. I don't run any lubrication at all, if you put it anywhere in there it always finds the belt. Which leads me to agreeing with one of the other posters, maintenance is huge. These buggers get so dirty and can be the reason for the flat spots. I take ours apart after each show( 1 practice 2 races) and clean them with alot of air and cotton rags. Make sure and check the plate in the back that holds the rollers in the variator so it isn't hanging up, I am not sure but seems to be the biggest problem I've seen. We have to run the stock exhaust pipe, but we took a really big drill bit and made about an inch hole through the muffler so it could flow easier. Do the Lt's have a restrictor washer in them, thats something else to check on.

 

Rollers: use stock rollers and all 6 like onebigzj noted. Drilling rollers is for fine tuning to a modded motor.
Why flat? The rollers are the wearing part. Like mentioned, dirt gets in there. 7 years on stock rollers is mighty fine if you ask me.
Grease: Suz used to pack it full. Now they use non (starting in 05). I recommend using a dab on each roller. This hold them in place during installation. A high temp bearing grease works well.
Springs:: Good idea to get a stock replacement torque spring.
The small shoe springs can be used on a LT but I mod them to work. You do not need those.
180 grams:: cut the shoe off approx 1/4 inch from the pads. Then drill the back to the desired weight.
The variator mentioned above is another "made for modded motor" things. I make them.
Piston:: I've never re-ringed a motor. Allways a new piston/rings maybe a bore. As you explained, your piston is wore. The dark down the piston tells us this. Things apear to be OK tho as your compression is right where I like it. 125 is stock comp. Head been shaved before is my guess. Head to piston squish (stock) should be at least.040+. It's .032 from the top of the piston to the top of the cyl alone, then the clearance the head has.
BTW, the stock pipe works well. I can still get double the HP and 11k+ on the stock pipe. Save your money there, no need for a pipe till you feel the need.LOL [img]i/expressions/face-icon-small-smile.gif[/img]

 

ok so this weekend I spent some time....a lot of time on the machine and finally have where I think it can be for right now. I had mentioned before I shaved .04 off of the head, port matched the cylinder, boysen reeds, Midwest mini gear and tensioner kit with chain, 90 main, dropped the needle, all restrictors are gone and now this weekend I went a little further.

I went ahead and put new rings on her even though I know I probably should have replaced the piston my bad. I had honed it a little so it should be pretty good. I was surprised to see one of the c clips on the piston sideways. This is a big no no as the they will fatigue over time and break then bam!!! Based off of everyones advice I went ahead replaced all of the rollers and lightened the rear shoes and of course cleaned up the faces of the clutches ect. I took the shoes and made them all 184grams by cutting off of the rear then from there I drilled where the 0 is on the backside of the weight till I got to 180grams. Almost forgot I replaced the clutch spring also as Jack was right there as the old one was about 1/4in shorter (sag). I got her all back together and it was much much better but still not right as it still bogged down low with 6 oem rollers. I tried to 4 rollers and that revved too high and never loaded the machine properly. So I tried 5 rollers even though it would be out of balance and it was really good. I ended up drilling all 6 of the rollers with a 11/32 bit (pressed the metal portion out for drilling) and ended up with a combined weight of the 6 altered rollers of 47.6grams. (5 oem rollers = 48.6 grams) After taking it for a ride it was great as it easily pulls the front end up and holds it for a little while and if I want of course lean back a little further and get it balanced and ride down the street if you want to with it up in the air. I think a combination of the random bolt ons and port matching and of course the gearing kit (geared up so it doesn't help out down low) that moved the powerband up a little which is why this seems to work out better than just doing the 180gram deal with 6 oem rollers. I'd imagine theres always room for improvement as Jack can take it to the extreme but for now I think it'll keep me happy. Hopefully this might help out some of you looking to tinker it for the adults. Thanks again for all of the help everyone!!!