I need some help with the clutch mods on an lt80. I have a pipe and a carb. When drilling out the rollers on the front clutch do I drill straight in to the roller or into the sides? Im assuming that I drill them to make them lighter. Also what size drill bit?

Next the rear clutch mods. What can be done? My local dealer does not know of any aftermarket springs for the rear.

Quad is used exclusivley in Glamis. Thanks in advance.

Scott

 

Clutch mods are pointless without motorwork such as port, polish, it all works together, so if want best performance have LT 80 do your motor work![img]i/expressions/face-icon-small-smile.gif[/img]

 

Haji is not completely correct. If you have added a pipe and carb, the engines performance should be much better, therfore justifying clutch mods. You should, though contact LT80, or another of the vendors listed on this board to get the right set up. You can drill the rollers to lighten them up, but knowing just how much is not that easy. There are stiffer clutch springs you can get, and can also drill holes in the clutch to lighten it up. But it is best to contact the guys who do this on a continual basis.

 

What mods if any are done and has the cylinder been bored, ported, or any headwork? Bubba

 

Just the pipe and carb for now.

Scott

 

Scott, hate to keep asking questions before I respond, but which pipe and which carb? Thanks

 

Cyco - Will you be at Glamis next weekend? I'd love to see that new Honda! Will be in Wash 11........

 

Sorry 2Gordons
I revised my profile. It is a CRF450R. Anyway I will be at Glamis over Prez weekend on Roadrunner.

Bubba 20mm Carb and a DG pipe. Looking to get rid of the DG though and go with the FMF.

 

Actually the DG will outperform the FMF. LT80 done testing and the FMF works great for a stocker and will pull to about 7000, but nothing after that. Remember that he does all his "national" engine work based on a stock pipe and carb. And let me tell you that it really rips too.

Here's a few things you can do to really increase the performance without a lot of money:
Buy a top end gasket set. Add another base gasket to the cylinder base. That will increase exhaust and transfer duration slightly and improve power. If you add a gasket then take the head while it's off and have it milled .030. If you do not do the base gasket addition, then take .020. That improves power, helps bottom end, and still maintains pump gas.
Now for the clutching:
You will need a gram scale. I went to staples and bought a digital non-expensive mail one that shows grams and ounces. Take the secondary clutch apart (the outside 17mm nut is RH thread, the very large thin nut behind that is LH thread). Cut the ends of the shoes back about 1/4 inch in front of the shoe material. Weight them to about 170 grams. The stockers if I remember right is a little over 200 each. That will increase stall takeoff speed. With the primary apart, take all 6 rollers out and look at them good. If they have bad flat spots them you need new ones. For an almost stock machine, I took 2 rollers and lightly pressed the inside metal roller out. Drill across the middle with 1/4 inch drill bit. Smooth the edges on a grinder or similar and put them back into the nylon sleeve. Use a good high temp grease and apply a liberal amount on all rolling surfaces. Dont get too crazy with it, but enough to do the job.
That is about all you can really do to increase performance on these without getting to the point where the bike revs and doesnt go.
One more thing to do is remove the stock reeds and replace them with a set of boyesens. They work much better. I hope this helps out,Bubba

 

Thanks for the info.