Velocity stack

mrbg

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Sep 22, 2014
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Recently installed velocity stack, on 66cc with NT carb 64#jet,needle clip on mid notch, no airfilter, about 100'ASL. I'm getting a little bog after it warms up. Any suggestions?
 
hate to say this but these engines aren't drag racers, just poopy put-puts.
frame your velocity stack and put an ESSENTIAL air filter on that thing!
 
does it bog at part throttle or full throttle?

These engines are plenty capable of making power, just because they don't from the factory doesn't mean they aren't built to handle it. the only issue they regularly have when a lot of power is being put through them is breaking top end bearing cages, which can be mitigated by installing a higher quality bearing
 
hate to say this but these engines aren't drag racers, just poopy put-puts.
frame your velocity stack and put an ESSENTIAL air filter on that thing!
On the way home I picked up a molded sink strainer that fits over the stack, I'll give it a try tomorrow if it doesn't work I'll put the stock one back on.
 
If it seizes up I've got another topend from a motor with seized bearings on the clutch shaft. I'm retired it gives me something to do
 
It bogs at full throttle. If I gradually accelerate it's ok. I'll look at the plug tomorrow I was thinking about raising the clip to the topnotch.guy down the street got a motor stuffed in a mtn bike no filter, carbs out of plumb so the throttle cable clears top bar. No problem oh well
 
with no other problems, bogs if you go straight to full throttle but not when you gradually increase throttle until you get to full is dirty jet, too lean, or float out of adjustment
 
It ran good before stack. I hadn't cleaned the carb in a while, stock filter had some oil in it. It could have some dirt in the bowl. I haven't had alot problems with this motor.I changed out clutch pads, chain wheel, cleaned the chain It got some miles on it though.
 
adding the stack is changing the engine. it's most likely a jet size or two too lean now.
 
Stack

adding the stack is changing the engine. it's most likely a jet size or two too lean now.
That makes sense it's getting more air, I'll try raising the needle. If that doesn't help I'll try a 66#.thanks
 
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