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The next step up

Posted: Thu Nov 07, 2013 3:48 pm
by Richjak
I am presently running the folloing set up in my bitza cutdown

late type 150 PX engine, polini 177 kit, 24mm (standard PX 200) carb standard PX 150 cut crank Polini exhaust pipe.
The engine casings have been matched to the barrel in the inlet ort has been opened up about 2mm.

Apart from the above everything else is pretty much standard except for uprated bearings and jets.
I am pretty happy with the performance so far, it wont break any speed records but its certainly respectable.
I want to take the next step up and wonder what should come next for a bit of cheap additional power.Crank or carb ??
If its carb it wil be a 28mm PWK item from Scoot RS or a Spaco 26mm standard type carb.
If its a racing crank from SIP, not really sure what the best one would be.

Would welcome any pointers and advice, the engine feels like there is more power on offer, what would be the best buy to do so.

Re: The next step up

Posted: Thu Nov 28, 2013 1:03 pm
by Richjak
Wow what an under whelming response 3 weeks and not a single bit of advice, was it worth even posting ?? obviously not.

Re: The next step up

Posted: Thu Nov 28, 2013 1:12 pm
by tea5ive
What about an ignition timing gizmo and a run on a rolling road ?.

Re: The next step up

Posted: Thu Nov 28, 2013 2:28 pm
by Svint1
Proper pipe along with the 28 carb.


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Re: The next step up

Posted: Thu Nov 28, 2013 6:08 pm
by H,POOL GADGE
Reed valve and a 28mm carb!

Re: The next step up

Posted: Thu Nov 28, 2013 6:13 pm
by santacama
What is the rotary valve timing?

Re: The next step up

Posted: Thu Nov 28, 2013 6:21 pm
by sean brady scooters
deffo swap the pipe first for a better one ,but retain the std 24mm carb ..but how your crank was cut and how the inlet was modified in conjunction will really affect its power delivery
also did you alter the gearing to take advantage of your kit ?

Re: The next step up

Posted: Thu Nov 28, 2013 7:00 pm
by Muttley McLadd
Richjak wrote:Wow what an under whelming response 3 weeks and not a single bit of advice, was it worth even posting ?? obviously not.
You could check your PMs now and then..

Re: The next step up

Posted: Thu Dec 05, 2013 6:06 am
by Richjak
Muttley - thanks mate just checked them your a star, sorry for the delay i have been travelling.

Quick update, i have picked up a cheap 28mm Dellorto carb so had some spare dosh for the 57mm flowed race crank.
Whilst i was on the SIP i have also ordered the polini upgear kit 23/64, but as per SIP advise i will run this as a 22/64.

When i get the chance i will fit all the above and see how we go.

Next i will be asking about jetting (have ordered a jetting kit as well)
Thanks for all the advice.

Cheers

Rich