Re: 50cc Puch build

Brandon Weiss (Detective brandon to you) /

> Chöschi21 C.K. Wrote:

> -------------------------------------------------------

> Never really had problems with the Brass Bushings, even at ~10'000rpm, i

> always had problems with the Bottom End Needle bearing on those cranks,

> the 2/3 Speed Sachs (pre 504/505) 25kmh Models seem to have the same

> problem, but there is a guy Racing here with a 30kmh Sach 503 and a

> Brass Bushing Crank doing i'd guess about 11-12'000rpm.

Well, that sounds fishy. It's a known fact that the bushing cranks fail. Just saw this on facebook:

Screenshot_20191020-150614_Facebook.jpg

Re: 50cc Puch build

Chöschi21 C.K. /

I mean i never had a Problem with the Brass bushing on my Puch Cranks, i always had a Problem with the Needle Bearing on the big end with those Brass Bushing cranks.

Re: 50cc Puch build

Brandon Weiss (Detective brandon to you) /

> Chöschi21 C.K. Wrote:

> -------------------------------------------------------

> I mean i never had a Problem with the Brass bushing on my Puch Cranks, i

> always had a Problem with the Needle Bearing on the big end with those

> Brass Bushing cranks.

well then you're probably not revving above 9,000rpm

Re: 50cc Puch build

Chöschi21 C.K. /

I think i am, doing 40 with 13:45 Gearing right now.

Re: 50cc Puch build

Jeffrey Strichart /

I believe you guys and what you say makes sense. It is what you might think would happen. Seems logical. But our mopeds defied logic then. All we did really was get them to breathe as much possible and change the gearing. We rode them every day and all over the place and nobody ever threw a rod or burned up a clutch. Not that I am aware of. I never did.

Re: 50cc Puch build

Jeffrey Strichart /

Sorry but I have not forgotten. I will update this with many pictures. Right now I am just getting it running right before anything. It has weak spark so I ordered points and a coil for it. Not much to photograph there. This is a winter project for me but it won't take that much time in fact it will probably be done before winter. I will need some good weather for test and tune. Thanks for your support.

Re: 50cc Puch build

are you worried about floating points above 10k rpm? At 17/40 you're looking at spinning roughly 11-11.5k to reach 60 and thats with no air resistance.

Re: 50cc Puch build

Jeffrey Strichart /

> Garrett H Wrote:

> -------------------------------------------------------

> are you worried about floating points above 10k rpm? At 17/40 you're

> looking at spinning roughly 11-11.5k to reach 60 and thats with no air

> resistance.

You make a good point (no pun intended). I know we used to do it but based on your calculations that could happen. Honestly I did not consider that. I could go 18/36 just for the top speed run so that is an option. Once I hit the magic number I am going back to near stock gears for around town. Probably 16/40. Also I am considering cdi. Do you think that could help? Would that be "cheating?" I have to do something as it is getting fuel and spark but the spark is very weak.(edited)

Re: 50cc Puch build

Brandon Weiss (Detective brandon to you) /

Bosch pint ignitions should give a strong, bright purple spark when set up properly.

Did you replace the condenser? Check your grounds too, make sure they're clean and solid. Make sure the plug boot has a good connection with the wire, same with the wire to the HT coil. Screw it in snug. If its loosey goosey, unscrew it, snip the ends so they're fresh and screw it back in.

Re: 50cc Puch build

Jeffrey Strichart /

> Brandon Weiss (Detective brandon to you) Wrote:

> -------------------------------------------------------

> Bosch pint ignitions should give a strong, bright purple spark when set

> up properly.

>

> Did you replace the condenser? Check your grounds too, make sure they're

> clean and solid. Make sure the plug boot has a good connection with the

> wire, same with the wire to the HT coil. Screw it in snug. If its loosey

> goosey, unscrew it, snip the ends so they're fresh and screw it back in.

I will do those things. I did get a condenser too. Should be here in a couple of days. Thanks.

Re: 50cc Puch build

I don't know anyone who has messed with running points at crazy rpm's but in theory you could double up the point spring.

Re: 50cc Puch build

Jeffrey Strichart /

I am going to give it a try and see what happens. Appreciate the feedback.

Re: 50cc Puch build

Chöschi21 C.K. /

I did, there are "High Performance" Bosch Point's floating around with harder springs, also, Kreidler did have a different one in their 50cc Shifters.

Re: 50cc Puch build

I had a tomos running a bosch flywheel that ran 11-12k rpm with no points problems

a single cylinder magneto like this has tons of dwell and makes more power the faster it spins, point float is not really a factor.

Re: 50cc Puch build

Jeffrey Strichart /

Check this out - it is cool enough as it is but scroll the comments down for a reply from Glen Baker. He reminisces about his moped in South Florida (where I had my mopeds) and running 60 mph. Maybe it was a South Florida thing. Because so many people there were running fast. If he was running 60 when we were I probably knew him but I do not recall the name.

Re: 50cc Puch build

Jeffrey Strichart /

I am going so attempt my 12v kit today, never done it before, wish me luck,

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