FR Ray
New member
I've got a 125cc engine on my buggy, 3 forward speeds and one reverse with a semi-auto shifter, a lot like this one. I'm mostly after good torque through the range, and the quietest exhaust I can find that won't hinder the performance too much. A few tuning and quietening questions below, thanks so much for your expertise!
1. It has a 38mm foam air filter I put on it. Can I extend the filter with a right angle bend (to make it exit vertically) and about half a foot of pipe on that? This is to keep it out of dust and dirt a bit more, and also give it fresh cool air.
2. The engine sits low behind the two seats, and doesn't get much air flow over and around it. Has anyone made a ram and funnel setup for something like this (just a big plastic setup near the shoulders of the driver and passenger), and seen an improvement in engine temps? Or would a powered fan directing air at the engine be a better option?
3. At the moment it has a 32mm exhaust flange, going to a 25mm pipe, into a small muffler with no packing. The noise levels are good at idle, but very noisy at higher revs. If I went to a straight 32mm pipe, put a Thumpstar muffler on (32 inlet, 38mm outlet), and packed it tightly with muffler packing, baffle and a spark arrestor, would that keep the appropriate back pressure and exhaust flow, and quiet it down some?
4. Any other tips on maximising the output of this little donk? I gave the carb (a PZ25K) a deep clean which it desperately needed, but it doesn't seem to have an air/fuel adjustment screw, only an idle adjust screw (which may do air/fuel at idle..?)
Any thoughts or tips much appreciated!
1. It has a 38mm foam air filter I put on it. Can I extend the filter with a right angle bend (to make it exit vertically) and about half a foot of pipe on that? This is to keep it out of dust and dirt a bit more, and also give it fresh cool air.
2. The engine sits low behind the two seats, and doesn't get much air flow over and around it. Has anyone made a ram and funnel setup for something like this (just a big plastic setup near the shoulders of the driver and passenger), and seen an improvement in engine temps? Or would a powered fan directing air at the engine be a better option?
3. At the moment it has a 32mm exhaust flange, going to a 25mm pipe, into a small muffler with no packing. The noise levels are good at idle, but very noisy at higher revs. If I went to a straight 32mm pipe, put a Thumpstar muffler on (32 inlet, 38mm outlet), and packed it tightly with muffler packing, baffle and a spark arrestor, would that keep the appropriate back pressure and exhaust flow, and quiet it down some?
4. Any other tips on maximising the output of this little donk? I gave the carb (a PZ25K) a deep clean which it desperately needed, but it doesn't seem to have an air/fuel adjustment screw, only an idle adjust screw (which may do air/fuel at idle..?)
Any thoughts or tips much appreciated!
