morbin

I did something here...

That's good to hear! I'm not sure what you mean with 1pm thing... is 1pm in the position of the green arrow?

Hi all, here are some pics of my crank for a Polini 177. Inlet phase is about 110 nOt - 66 vOT. I made this modification most of all for the blowback problem at low RPM and to optimize flow, now I'd like to know, will it work well? Any suggestion from you experts? Any comment is wellcome! Gruss Matt

Hi all, I did it myself and have to say I'm very happy! I noticed immediately a feeling as if the engine is capable of burning gas better, this resulting in improved fluidity of driving and feeling of more torque… In few words for me a success, little money much satisfaction! Here's my circuit, I'm only having some problems with it because it disconnects from time to time and the engine turns off... have to find a safer way to connect it... Ciao!

If you buy a bitubo for disk brake it will fit the drum too, viceversa is not possible... ciao

Hi all, I'm looking for a Cosa Clutch 21 teeth reinforced. Please contact me by PM Gruss, Matt

Sorry all, and what is best squish clearance or its best range with Gravedigger's head on the Polini 177? Matt

Thanks all, and most of it goes of course to Olli ETS and Johnny13!! I'm very happy, I just received the piston and looks very strong and rings are so thin, I'm deeply looking forward to try it!! Here are some things I'd like to know, maybe it's silly but I bought a piston with 63,5mm on it, this is the measure I should work the Polini cylinder, isn't it? I want my Polini for touring and I measured 63,4 on the piston, therefore is 0,1mm clearance right? Just to know, would it be safe to drive with let's say 0,08mm of clearance? Ciao! Matt

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Ok, now I see. Anyway a question is coming to my mind... I knew that the valve area must be the same size of that of the carburettor (or at least a little smaller in order to make gas flux faster...). SI 24 area is 14*14*pi = 452mm2 therefore I should go for such an area on the valve (if valve width is 11mm length is 41mm, if width is 12mm length becomes 37.7mm, with 13mm length is 34.8...). Ovalizing then makes internal area bigger than carburettor area... so is ovalizing helpful to make valve area bigger, is this done only to switch in any moment to let's say a PHBH 28 or this is done for blowback issues? Gruss, Matt

Thanks all. The pdf file is very interesting. So if I understand right the ovalizing takes place only at the bottom of the carb, right?

Hi all, I'm trying to understand how to ovalize my SI 24. I have problems with German (DA...) I'd like to know if there are some posts with some nice and easy pictures... Will my Polini 177 with GS piston & Gravie's head benefit of this? Thanks a lot, Gruss Matt

It is only a matter of engineprefix. In Italy the engine prefix is written on the roller's documents, and my roller is a P150X, so if the code is not the same you could run into trouble...

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Anyone with VLX1M motorgehäuse?

I measured values in between 140-180 VAC, I'm gonna try the circuit Gruss, Matt PS. my other tester indicated around a 20V value, maybe it all depends on the tester you use...

Hi grazie a tutti, I'm looking for a PX 150 case though, and VNL2M is for 125 and the case will be for a valve inlet engine...

Ok thanks, but if you check you'll make me a favour... I noticed that 200 crank shoulders are wider that 125/150s' so I think that with 200 shoulders and 125/150 rod I could widen more the valve hopefully for bigger carburettors. Has Anyone tried this? Gruss, Matt

Hi all, is it possible to put the rod from a PX 125/150 crank into a 200 crank? I mean, is bearing size at the bottom of the rods the same? Thanks, Matt

Hi KTy ;) I'm curious to try this modification... About the homemade nology wire I thought about using a wire from a Television (the one that is intended for very high tensions) but still have to find the way to connect it as it is too thin... :P Gruss, Matt

:wasntme:

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Hi, I'm looking for a PX 150 case (first type, with external wheel oil seal) and 125/150 crank. Thanks, Matt

Hi my friend's engine works well with: Idle 52 Needle X2 second position from top main 122 (with Leo exhaust you'll need more than this) AV 264 gas valve 40 Greets, Matt

Hi KTy, I'm no PHBH expert but I'd start carburation with circlip in middle position... Matt Ps. going to send you a PM