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Small Carbs
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@moto64 avatar
Moto64
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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Location: NYS
UTC quote
Would putting a 20/20 on a stock VBB 2-port 150 make any noticeable difference over the 20/17? I see that a 20/17 was stock on a Sprint Veloce so maybe not....
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helikiwi
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64, 65 and 66 Smallframes and a Sportique
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helikiwi
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UTC quote
When I first got mine, as an easy cheap boost. 20.20 carb and a stock PX150 exhaust. I had these lying around from an upgrade. This made a noticeable boost.
⚠️ Last edited by helikiwi on UTC; edited 1 time
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qascooter
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79 P200E (Ruby), 62 Allstate (B-62), 63 VBB (Storm)
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79 P200E (Ruby), 62 Allstate (B-62), 63 VBB (Storm)
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UTC quote
Yes, there is an improvement. Small but noticable.
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ditchdrift
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UTC quote
I would say yes. Worth it. I reamed my 16.12 out to 16.16 and it was very noticable. This was on a pk50 so I'm assuming the difference would be more on yours.
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Moto64
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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Location: NYS
UTC quote
ditchdrift wrote:
I would say yes. Worth it. I reamed my 16.12 out to 16.16 and it was very noticable. This was on a pk50 so I'm assuming the difference would be more on yours.
I did see your post on that. 150ccs is just about the minimum for these roads and a little bit more on this bike would be nice. I'm looking forward to seeing how it goes. I bumped the carb up one size on my LD150 and although it didn't move it into the "tuned" category, it was a satisfying improvement.
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jedihunter
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66 bluebadge, 73 primavera,2x 74 rally,79 p200e 64 gl 306 2x 64 vbb
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UTC quote
I have a 20/20 carb you can have if you want to try it.
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Moto64
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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Location: NYS
UTC quote
jedihunter wrote:
I have a 20/20 carb you can have if you want to try it.
Thanks, I have located one here.
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66 bluebadge, 73 primavera,2x 74 rally,79 p200e 64 gl 306 2x 64 vbb
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No worries. Just trying clear out some stuff.
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Moto64
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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Location: NYS
UTC quote
helikiwi wrote:
When I first got mine, as an easy cheap boost. 20.20 carb and a stock PX150 exhaust. I had these lying around from an upgrade. This made a noticeable boost.
Helikiwi, You don't, by any chance, know how you have it jetted do you? If you are on the Riviera, I assume that is seal level? I am pretty close to it here.
I am looking at a database and from what I see, only two models came with 20/20s. The PX125 and the Rally180 which is quite a spread.
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helikiwi
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64, 65 and 66 Smallframes and a Sportique
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UTC quote
I'm running a 105
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Moto64
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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UTC quote
Wow. Just went out for a short ride around the neighborhood (all hills) and I must say this motor pulls much better and the 20/20 is a remarkable improvement. I think I have to play with the jets a bit and drop down some on the 105 but, so far, I am impressed. After farting around almost all day with the Mikuni on a little Yamaha dirt bike, I just popped the new carb on the VBB and ended the day with a smile. Instant gratification!
Thanks.
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endoftheroad
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endoftheroad
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UTC quote
I believe the stock carb for a Sprint Veloce IS a 20/20.

That's what my 69' had when I got it.

Just saying...
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@moto64 avatar
Moto64
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
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Location: NYS
 
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'64 Motovespa 150S (177) , '65 VBB, '66 Allstate SF, '66 180SS, '58 LD 125 (150)
Joined: UTC
Posts: 2472
Location: NYS
UTC quote
I am just going from this sheet. I see I missed the PX150.
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Birdsnest
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VNB VSC VSX Li150 09C C125 - (vmb vse v9b)
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Birdsnest
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Now just add a SIP road 2 and get yourself a first class ticket to torquetown!
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az_slynch
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'07 GTS250, '07 LX150, '81 P200E, '78 P200E, '74 VBC1, '64 V90 and 3 Ciaos
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UTC quote
Moto64 wrote:
After farting around almost all day with the Mikuni on a little Yamaha dirt bike, I just popped the new carb on the VBB and ended the day with a smile.
This is usually the deal with a Mikuni flatslide. The whole (jet number is flow rate, not bore size) faff with jetting is a bit of a nuisance too.
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