pug 103 + sha tuning help

pug 103 stock except for lightened variator wts and a SHA 15.15 with matching mallosi intake and de-restricted stock pipe...top speed is around 32 if i let it wind out downhill.

i've been trying to get this thing tuned but i need some feedback from the experts.

runs fine but i was worried i was lean, chked the plug it's nice tan color after running a 65 jet and taking most of the screens out of the airfilter (one screen with a scothchbrite pad...)

anyway, the thing goes slow uphill (15mph) and the top end just doesn't seem there. played with different combos of screens...if I added screens it bogged...if i removed some it rode much better (higher top speed and better climbing)...if i upjet it really bogs down.

now, I've down jetted (i'm a mile high so that's expected) to a 63 jet and one pretty open screen. it really seems to be going in the right direction but i kinda don't wanna sieze the engine, plus, there really is barely a screen in there now and i'm thinking i might be sucking in to much dust. thinking of kitting this winter, replacing seals and gasket and maybe a new pipe...don't wanna lose the kickstand or pedals...

any opinions??? I'm thinking i should downjet further for now and maybe throw some more restriction in the airfilter...am i stupid?


Re: pug 103 + sha tuning help

I have the exact same set up and mine does 50 on a slight downhill with 4500 miles on original engine, but I'm at 650' elev. I think you are lacking air up there. I took my peds to a ski resort once, and they ran much slower even after rejetting. However Ithink you're jetted pretty close, but you may want to check the timing.

Re: pug 103 + sha tuning help

yeah...that's in the works and new points too but I may wait till the winter teardown for that....the thing that bugs me is that the common theme here is I should be going faster for as well as it runs right now

mel, how many screens are you running? and what jet? i may drop to a 61 and see what happens...

anyone from high elevation have a pug?

Re: pug 103 + sha tuning help

Did you take off the 2mm lip on the top of the exhaust port ?

Re: pug 103 + sha tuning help

no screens out stock filter, exhaust lip gone, can't remember jet

Re: pug 103 + sha tuning help

have yet to grind the lip off...can it be done with engine on the bike?

Re: pug 103 + sha tuning help

nevermind...found the answer...guess I could pull the head and cylinder to do it but if I'm gonna do that during winter teardown...i'll just grind it then.

was thinkin tho' what if i just pull the head, drop the piston down past the exhaust port shove a rag in there to keep the shavings out, dremel and vacuum it out...probably a bad idea...

Re: pug 103 + sha tuning help

not worth the risk, once the head is off, the cylinder just slides off, worst case is you may need a new base gasket. you may also find the exhaust port was carboned up too.

Re: pug 103 + sha tuning help

true...may give it a shot this weekend...

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