Hello all,
Just started to race Hare Scrambles and my sons LT80 could use a few upgrades to keep him with the pack. Here is what it's currently running and any input would be greatly appreciated!!!
- FMF Fatty with powercore silencer.
- Boyesen 2 stage reed
- Stock front variator with all 6 weights @ 10 grams each.
- Stock rear clutch with shoes lightened to 188.7 grams each.
- Stock carb with 20 PJ and 95 MJ.

This is the setup that I bought it with. Right now he is having issues with starting on an incline. The quad will just rev a little and then stay at a steady RPM but not go, it doesn't roll back either.

Thanks in advance for any advice.

 

What's your budget?

 

I haven't really set a limit as of yet. I don't want to end up spending what I could purchase a set up Nationals quad for.

 

Well...I guess I'd first question the clutch mods...I say that as it's my understanding the pipe & reeds don't buy ya much in HP and probably nothing in RPM...so raising the shift RPM may be costing more than it's producing (stock, that little 80 has quite a bit of meat down low)...


But, since they are done, I guess I'd look to elsewhere for power. You mention 95 mains...what's the plug color at a WOT plug chop? If not light tan, then you're fat (rich) on top...drop to a 92.5 or even a 90...that's a cheap one...I'd also check compression with a good tester...if racing I wouldn't settle for anything under 120 PSI


Next you're looking at porting/polishing the cylinder and shaving the head. Jack Moore (LT80) does this work and has been racing these things for ages...he did his stage 2 on my LT (that also includes opening the carb and reed cage in addition to the head/cylinder work)...reasonably priced and the workmanship was top notch...that mod definitely requires clutch work (also part of Jack's Stage 2 kit) as the RPM range is bumped up quite a bit...


What else...I've seen big bore kits...I think to 110cc...but not 100% sure on those. National kits (like a stage 2 but much more aggressive porting - need race gas). Then there is alcohol...but that's getting ridiculous...


Here is my LT80...there is soooooo much more that can be done

 

That's a good looking machine. I like the front suspension mod.
I will be shaving the head this week as recommended by Jack. Next will be playing with the front variator weights. We have this coming weekend off from racing so I have enough time to tinker before he races again.
I will have to double check on the plug condition. I know the last plug I pulled out was black but not gunked.
I already run 2 gallons 93 and 1 gallon 110 leaded race fuel. It's the same mix I use in my YZ250...40:1 Amsoil Dominator

 

With stock compression there is no need to race fuel. If the plug is black you are running rich...2 stroke oil is made to burn clean and is not causing your plug color...

 

Pulled the plug after a short run today and it's brown/slightly black near the electrode.Compression tested and got 120-121psi. I'm shaving the head tonite at work so once I get it back together I will be able to test the jetting again. I went ahead and ordered a 92.5 and a 90. Any idea what comes in a stock carb? I have one and wondering if I didn't have to buy one that I ordered.

Thank you for all of the advice so far!!!! Can't wait to get it running again so I can tinker some more!

 

Stock main jet is 92.5