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Discussion Starter · #1 ·
Another Carb project, sleeving the 19 to 17mm in the rear bore, and mounting it to the Polini ZPF/BZM aftermarket intake, on Polini CF .025" reeds on V- block. The stuff that comes from Germany with the billet cases, SKF bearings and seals. I think the 19mm is to big, that is why I am cutting down the rear bore, but the front will remain unchanged 34mm.
 

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...... sleeving the 19 to 17mm in the rear bore, ....

I think the 19mm is to big, that is why I am cutting down the rear bore, but the front will remain unchanged 34mm.
... ???... why you do this ?? I don't understand ...

The manifold beside the new case is for PHBG- carb types ( all PHBG typs have the same outer diameter by slip- in mounting )

The ( china ) airfilter on the pic is also not usable for PHBG types


Put this carb into/on your C1 , with the right manifold (25/23) and a few little modfications ( 2) + change the innerlife into Dellorto genuine parts- but the right ones ;-) before; after that it should run
 

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Discussion Starter · #4 ·
That's my broken C1 manifold, I put it the to show what the manifold looks like, I read your info about the 17 & 19mm PHBG, PHVA.
That manifold is getting ground flat and am mounting my 19mm HDA223B Walbro pumper carb that's mounted to an alum Cag Walbro manifold bolted & sealed to the broken C1 manifold ( 46cc Blata ) copy bike. Going on the C1 engine. If I like it will make my own manifold out of 1/4" to 1/2" thick alum to bolt up to the Cag manifold & carb.
 

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Discussion Starter · #5 · (Edited)
Re: Update 1, 19/17mm Sleeved Dell PHBG Copy carb to F1 Billet Case Cag

Finished the carb today, long day, 12hrs of Sebring Florida, where Corvette past the lead Ferrari in the GT class with just laps to go, and the Nascar Nationwide at Bristol Tenn. & Kyle Bush 1st in the Monster Energy Toyota, Boooo., and finishing the carb,lol. More info about it on my Billet Case Cag eng. thread.
 

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Discussion Starter · #7 ·
It's going to slip right in the polini copy intake manifold that came with your billet Cag cases. I did not touch the OD of the carb, I sleeved the rear bore from 19 to 17mm, cause when I ran this carb as a 19mm on my B/B Cag Boosted306 racing engine, worked for days, to much air flow, and have to run a big jet to get the right mixture then it just bogs out. I think I can manage 17mm easier and it is plenty of carb for a 49cc engine. I have another 19mm rep carb just like it stored,lol.
You gave me a way to get the cheap new China crank bearings I put into the new cases w/ a plastic tipped hammer. I have new SKF bearings I want to put back in the Z1/V1 one ring 40mm piston engine before I put it back together, so into the oven,lol. Is 350 degrees F. to hot??
 

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Discussion Starter · #9 ·
Thanks, that help alot. He confused me alittle since you freeze the bearings and heat the cases how do the bearings get to hot, when you drop them in the hot cases,lol. So, I will start at 275 F. and see how that works.
 

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I only wrote that, if sometimes you have also warm up the bearings, then also only at 100 C - max 120 C deg.

This is needed somtimes to set in the crank afterwards.

for example:

cag case ...
bearings into the freezer ( out of the package , naked) - 1 day
case warm up , 10 min. at 100 C ,
then take out , bearing put horziontal / straight into the case bearing seat ( no skewed , if not try again). It falls automaticly inside , if not it's not cold enough . Cool again a little and try again .
china crank after that needs no preparation before because itself has so many / big tolerances that it will easily go through the bearings ( in normal room temp.) - no problem.

Now another case; you need it for other brands cases and brands cranks :
do all the same before - see above -
but then you have to put once more the case, with the already installed bearings complete into the oven again ( also only 10 min at 100 C !!) .
brands crank cooldown before .

Now you have also the cold/warm method to get the crank trough the bearings.

This is needed because brands cranks have a better and stronger bearing seat as it should be, not as the simple china cranks .

Also therefor the oil seals will mounted always at the final step!!

And for this I wrote yesterday : don't heat up bearings over 160 C ;
after that they are dead. Its the rule .

You understand it now ??

who knows all this, can also work with ice-spray and an industrial blower, its for people who worked " every day" with this things.
( but its a little longer and you should know the times and degrees, so take the oven method ! - and an oven and freezer is in every house or appartement , not everbody has industrial ice cooling spray & industrial blower)
 

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Discussion Starter · #11 · (Edited)
First I will get the bearings in the cases and try to freeze the crank to see if the go thru. The hard part is getting the crank thru the cases and sealing the middle, not sure how that will work. One step at a time,lol. Yeah, no ones checking the parts on the China stuff, I have received new cyld that was warped.
 
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