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Re: MB Reed Block for Piston Port.
Posted: Tue May 31, 2011 8:40 am
by Craig H
When i had it dyno'd first I had a PM pipe on and we only did one run without the air filter on and dont think there was anywhere near as much spit back as I have now with the JL3 but not 100% sure as it was 4-5 months ago. Maybe it is the pipe hopefully Diablo will sort it out this week. FOCKIN SCOOTERS££££££££££££
Re: MB Reed Block for Piston Port.
Posted: Tue May 31, 2011 8:45 am
by lozmondo
coaster wrote: I still think it's a blinding kit though, a reed valve will cure the spitback but it's not just a bolt on job, the cylinder will need to be re-worked otherwise you will loose a lot of top end.
What re working ? mine doesn't rev like it did prior to reed valve .Im still running the Ancilotti and 24mm TM,
Re: MB Reed Block for Piston Port.
Posted: Tue May 31, 2011 10:29 am
by J1MS
Larger inlet port & piston cut and modded (similar to Jason frosts in his link) this will let the port breath better & for longer...
Re: MB Reed Block for Piston Port.
Posted: Tue May 31, 2011 10:54 am
by lozmondo
I is running a Jap pison with windows, has a boost port. I was thinking it was over geared but its running LI125 17 tooth front ?
Re: MB Reed Block for Piston Port.
Posted: Tue May 31, 2011 10:58 am
by J1MS
lozmondo wrote:I is running a Jap pison with windows, has a boost port. I was thinking it was over geared but its running LI125 17 tooth front ?
Have you enlarged the inlet port height or is it still standard.
Re: MB Reed Block for Piston Port.
Posted: Tue May 31, 2011 11:15 am
by lozmondo
Enlarged and matched to reed block.
Prior to new piston and reed block it was a standard SR piston..with added slap!!..running around 175 exhaust 150 inlet 124 transfer.
I am guessing the now shorter barrel for the Jap piston has dropped the exhaust timing? it runs a 60mm 107mm rodded crank. It has been an engine developed over time in stages, hence the mix of components and just to see what could be achieved with these kits .
It pulls like a train, just runs out of steam a bit ??
Re: MB Reed Block for Piston Port.
Posted: Wed Jun 01, 2011 11:38 pm
by coaster
Jason, if it isn't a daft question, I'm using the 6 petal malossi petals and have been running it with the carb in a horizontal position. I'm now wondering if it is supposed to be the other way up to provide a downdraft but it would mean the PHBH being at a sidaeways angle, is that right do you know
Cheers
Colin
Re: MB Reed Block for Piston Port.
Posted: Fri Jun 03, 2011 8:37 am
by jason frost
coaster wrote:
Jason, if it isn't a daft question, I'm using the 6 petal malossi petals and have been running it with the carb in a horizontal position. I'm now wondering if it is supposed to be the other way up to provide a downdraft but it would mean the PHBH being at a sidaeways angle, is that right do you know
Cheers
Colin
Do you mean turn the rubber upside down ?
Re: MB Reed Block for Piston Port.
Posted: Fri Jun 03, 2011 8:55 am
by coaster
jason frost wrote:Do you mean turn the rubber upside down ?
Yes, that's what I meant, with the rubber inverted you get a direct path straight into the cylinder. My 28 PHBH will fit but would need to sit at a very twisted angle as iut's quite a tall carb and the toolbox and long range tank get in the way
I've since looked at Mr B's blog on Facebook and all the pictures on there show the rubber fitted in the horizontal position so I guess I was right in the first place
Cheers
colin
Re: MB Reed Block for Piston Port.
Posted: Sun Jul 10, 2011 4:23 pm
by bigmuff
lozmondo wrote:I is running a Jap pison with windows, has a boost port. I was thinking it was over geared but its running LI125 17 tooth front ?
Loz,
What piston are you running, and how much was the barrel shortened?
I am running a SR175 ported by Geoff Stephens at present. Crank is 60mm Mec with 107 rod. Have a homemade reed valve manifold with MB cage/rubber i want to use on it and thought RD350 piston may be the way to go. Do not want to rip engine apart to re-rod.
Cheers, Andy.