Boyesen/Polini 4 Petal Set-up

Anyone done a Polini/Boyesen 4 petal reed valve set up on a Puch? I did a search and found zero. It took some work since there are no screws to install the reeds but I'm starting to think maybe this was a dead end here. It's all set but for some reason it's not pulling any fuel. Figure after a 90' run since I have no pedals that the plug would be wet. Tried starting fluid and it kicked a few times but nothing really. BTW, this is an all redone bike which makes guessing shit. I have everything hardwired and it's got spark though I'm honestly guessing the intake is what's not functioning properly. Stator is full and gaped at .016, new plug, 64cc polini w/21mm dell. Help me, please.

Re: Boyesen/Polini 4 Petal Set-up

Did you do any porting?

Re: Boyesen/Polini 4 Petal Set-up

Just matched the case was all.

Re: Boyesen/Polini 4 Petal Set-up

I just put one on my polini. since tightening down the intake (it has the hex nuts with washers that basically tighten from the outside) can be hard, I used a little bit of silicone underneath around the edge and then tightened. That was to ensure that I had a really good seal with no leaks. It doesn't take alot, but I've had no problems.

As for the boyesen reeds, you have to custom mod that. The polini cage I got didn't have screws so i basically cut the stocks reeds off. I drilled new holes in the same spot and tapped it to the size screws i was using. After I instaled and everything fit, I went inside the reed cage and cut off the excess screw that ended up sticking out and being in the way of air/gas flow. I then used blue locktite.

no problems, runs awesome.

Re: Boyesen/Polini 4 Petal Set-up

That set up likes a BIG! jet....piston is not upside down ? check all sealing surfaces for casting flaws and misalignment, file and dremel to make it right...sealant is key...I like that high strength grey silicon for intake stuff...pull carb- spin mag by hand with finger on intake...is there a good pull...that set-up rips when you get the bugs out ...let me guess no kickstand either...? cuz when it does fire with rear brake throttle blasts youll get that bike close to perfect quickly...take all that stuff(kickstands pedals) off after you dial it in...Da Cat

Re: Boyesen/Polini 4 Petal Set-up

Ok. All the things in the above posts were done prior. I removed the carb w/boot and there was not really any fuel that looked to have been going through??? Got gas, valve is open. Just isn't pulling it through. Pulled the plug and put my finger in the hole and it had good pull. Running out of breath and ideas. Thanks for all the help so far.

Re: Boyesen/Polini 4 Petal Set-up

recheck your timing?

I had the same problem on mine at first.

I have the hpi cdi though. It came lose and timing was off.

i have a 19 phbg, and my jet is 98 right now. The color is close to perfect (in fact I may down jet one size).

been blasting full throttle (crusing 55 easily) for a while now on 60:1 mixture. no problems. spark plug color is same coffee color every time pulled.

also did you take the disc out of your phbg?

if your jet is too small like shaw stated you'll be getting nowhere

Re: Boyesen/Polini 4 Petal Set-up

Got it going. Thanks for the advise on that jet. It has a 98 in there now but since it's a 21 maybe I should look into 100's? This is all my fault. I had installed this back in 08', yes I have been building this bike since last May and the reed block bolts were not as tight as they should be and no ultra gray. After it caught I noticed fuel seeping were the cage and cylinder join and shut it down. I sealed everything but that sealing surface. Should be back together here in a few and hopefully enjoying a new ride. Glad to know that other folks had done this before with these reeds since there was not much talk of it.

Thanks-John G.

Re: Boyesen/Polini 4 Petal Set-up

no problem glad to hear.

I would assume that you are going to need a slightly larger jet considering that carb. I have alot of work done to my bike and 98 is working almost perfectly (I'm in NC for elevation and location reference).

good luck tuning, and blast away!

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