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Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sat Sep 14, 2013 9:33 am
by MattsDad
Liner is temporary, it'll be getting an aluminium one.
I'll stick it on this engine in a couple of weeks which is more similar to Dan's.

Image

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sat Sep 14, 2013 8:17 pm
by GP240
hey-up T, hope the erectile problem straitens itself out haha.

cant believe your trying to make the tourer go faster, nearly ripped me arms out of me shoulder lol.

oh an av another glass of red an put up some more graphs of the A/F you worked on.

Vespa BGM MRB Clubman - 30.21hp

Posted: Sat Sep 14, 2013 10:12 pm
by fairspares
GP240 wrote: oh an av another glass of red an put up some more graphs of the A/F you worked on.
id like to see that to as it looks identical to the one Ben@AF and myself built.

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sun Sep 15, 2013 9:43 am
by GP240
Sorry Shaun, I thought your engine was the one Tony worked on, my mistake oops.

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sun Sep 15, 2013 11:58 am
by MattsDad
Sorry I didn't mean to cause any confusion.
You lose track don't you, because on that photograph of a graph some text is deleted by black marker pen so I'm not sure.
I don't think its the same engine though because on this thread its stated the initial sequence of events and tune to work with was:

"Race Rapido fast road , 72mm bore, 58 stroke ,franspeed race pipe ,37mm koso, 10.8/1 comp head, 1.2mm squish, timings: standard transferes 130 with casings matched 240 inlet , 189 exhaust, fitted with reed block and single boost port , green line with bgm rd reeds 23.2 bhp , blue line straight swap for v force rd 350 block 26.3 bhp , red line slight fiddle with jetting 28 bhp , il put up the torque figures when i can find the graph".

http://scooterotica.org/forum/viewtopic ... 45&t=23872

The one I worked on was completely different and I know because I was there doing it and still have all my notes, so it mustn't be the same:

1. 08/09/2012 - green line - 126/187 durations, 0.10 base, 1.60 head, 1.55 squish, 23.23 hp
2. 28/09/2012 - blue line - 130 / 188/9 durations, 1.10 base, no head gasket, 1.10 squish, 26.31 hp
3. 13/10/2012 - red line - All same as number 2 with addition of Vforce 3 Tassinari, no jetting changes whatsoever - 28.06 hp

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sun Sep 15, 2013 7:35 pm
by drunkmunkey6969
MattsDad wrote:Liner is temporary, it'll be getting an aluminium one.
I'll stick it on this engine in a couple of weeks which is more similar to Dan's.

Image

Great result that, I love the curve. Whose Dyno is it?

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sun Sep 15, 2013 7:49 pm
by Darrell Taylor
how did the mjp compare to the dynojet on shauns sprinter dan?

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sun Sep 15, 2013 10:18 pm
by drunkmunkey6969
Darrell Taylor wrote:how did the mjp compare to the dynojet on shauns sprinter dan?
You'll have to ask Shaun, as posted in the relevant thread.....i can't comment without Shaun's permission.

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Sun Sep 15, 2013 10:36 pm
by Darrell Taylor
ta ,will see him at weekend

Re: Vespa BGM MRB Clubman - 30.21hp

Posted: Mon Sep 16, 2013 2:49 pm
by Darrell Taylor
MattsDad wrote:Sorry I don't really use or own standard pipes but hopefully will be doing an expansion comparison next week.
Its new engine build and not standard. Not welded, 57 stroke, Vespatronic, reed, centred head, and TM carb.
Its got packing options to make into a touring tune also so will graph that too.
Here's the torque which shows efficient bmep peaks so happy will that and more than surprised the pipe revs through this far:
Image

just noticed on this graph of the lambretta dyno put on by accident that the correction factor is missing/cropped off the picture ,i took a look at the old rapido 42bhp post and found the correction factor shown is sae 1.21 whereas the vespa graphs are 0.96 / 97 which is more or less what uk weather corrects to fluctuating from min 0.95 to 1.05max

this means the power figure shown is inflated by 0.25 which corrects to a real figure of 31.34bhp be worth asking the dyno guy for a new graph with the the appropriate correction applied

if the original 26.31 graph was 0.97 and the 1.21 applied you,d see 32.8

figures arent perfectly calculated ive applied 25% for the 0.25 which is close


id presume the old graph at 26.31 was around a 0.97 correction
and new graph with new tune 31.34 with 0.97 correction applied so a healthy 4bhp increase all the same