VBB Lockdown Project -- Maybe I'll finish before lockdown...
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Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2575
Location: London UK
Sat Sep 19, 2020 4:12 am quote
The No.4 slide will work out ok on this. If you are sure 125 main jet is a bit rich, then you will need a BE5. Stick to pilot jets that end in 120 starting with 50/120 and see how it goes.
Good you are just using AFR as a rough guide to see the direction to go in. This is what they are good for.
Would be nice to get this done before the move. If there are scooters in TN you want to be able to keep up
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Sat Sep 19, 2020 6:14 am quote
I'll check the existing slide and order a #4 if I don't already have one.

I'd kind've come to the same conclusion about using */120 idle jets based on reading old threads around here. I'll probably give that a try later today, even though I need to be going through and clearing things out for the move.

I like to use the AFR to confirm that changes worked as expected and never normally go further than around the block with it in place.

And, lastly, if I need to keep up with anyone...there's always the Sprint which will hold its own well past the point that I fall back because of the dive-y front fork

I do find it fascinating that the 1/4 throttle range seems to get so little attention on here, too.
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2295

Sat Sep 19, 2020 6:46 am quote
This is getting interesting. Your video didn't sound that bad when you rode it . Mine seems to be a lot shorter on 1&2 before I feel the need to shift, yours sounds nice to me but what do I know I'm still trying to find out what blubbering actually describes.

Question if its not to much of a bother , Jack had mentioned sticking to the pilot jets that ended with the 120 , how do the second numbers distinguish themselves from each other ie 120, 140, 160? I know I got a lot of searching and learning to do
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Sat Sep 19, 2020 7:12 am quote
The pilot jet is a little mini jet stack combining an air corrector with a fuel passage, so the 150/60 is a 150 air corrector with a 60 fuel jet.

In my case, I'll try a 45/120 or a 40/120 next and see how that helps.

I'm still a little unsure on how much (if) the AC side actually flows past idle into the quarter throttle, but it'll be interesting to see.
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2295

Sat Sep 19, 2020 8:20 am quote
chandlerman wrote:
The pilot jet is a little mini jet stack combining an air corrector with a fuel passage, so the 150/60 is a 150 air corrector with a 60 fuel jet.

In my case, I'll try a 45/120 or a 40/120 next and see how that helps.

I'm still a little unsure on how much (if) the AC side actually flows past idle into the quarter throttle, but it'll be interesting to see.
Ahhh ok so there's actually an air corrector for the main jet and the pilot jet. Ok so the bottom part of the pilot jet is fuel and the top Air Corrector and the bottom an be drilled to go bigger but nothing can be done with the AC part of the pilot jet .
Molto Verboso
79 P200E, 62 Allstate, 2008 Stella
Joined: 11 Jan 2006
Posts: 1946
Location: Florence, OR
Sat Sep 19, 2020 8:20 am quote
chandlerman wrote:
The pilot jet is a little mini jet stack combining an air corrector with a fuel passage, so the 150/60 is a 150 air corrector with a 60 fuel jet.

In my case, I'll try a 45/120 or a 40/120 next and see how that helps.

I'm still a little unsure on how much (if) the AC side actually flows past idle into the quarter throttle, but it'll be interesting to see.
This is excellent info. Thanks. I'm interested to see also how it affects the 1/4 throttle dead zone...
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2295

Sat Sep 19, 2020 8:22 am quote
qascooter wrote:
chandlerman wrote:
The pilot jet is a little mini jet stack combining an air corrector with a fuel passage, so the 150/60 is a 150 air corrector with a 60 fuel jet.

In my case, I'll try a 45/120 or a 40/120 next and see how that helps.

I'm still a little unsure on how much (if) the AC side actually flows past idle into the quarter throttle, but it'll be interesting to see.
This is excellent info. Thanks. I'm interested to see also how it affects the 1/4 throttle dead zone...
I concur this is most excellent information, Scott we are getting so much smautter
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1979
Location: california
Sat Sep 19, 2020 8:39 am quote
CM - as you get richer on idle- I would expect it to diminish your flat spot.
As it approaches getting rid of it - you may find that instead of a hard flat - you will have a spot on your throttle that seems to 4 stroke if you try and cruz - at say very low speed with just 1/4 open.

On mine - I found its the handoff spot between the idle and main - and can be a challenge to get just right.
The VBB is a nice looking bike.
Will be cool to show up with that!
bodgemaster
63 GL, 76 Super (x 2), 74 Primavera (x 2), 06 Fly 150
Joined: 26 Sep 2013
Posts: 5579
Location: So Cal
Sat Sep 19, 2020 8:46 am quote
This probably doesnít need to be said, but Iíll say it anyway as a reminder ...

Before messing with jetting or making adjustments to the mixture, make sure the engine is AT OPERATING TEMPERATURE.

That doesnít mean riding up the block and back. It means heat soaked. If the engine isnít warm youíre not hitting the target.
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2295

Sat Sep 19, 2020 9:55 am quote
charlieman22 wrote:
CM - as you get richer on idle- I would expect it to diminish your flat spot.
As it approaches getting rid of it - you may find that instead of a hard flat - you will have a spot on your throttle that seems to 4 stroke if you try and cruz - at say very low speed with just 1/4 open.

On mine - I found its the handoff spot between the idle and main - and can be a challenge to get just right.
The VBB is a nice looking bike.
Will be cool to show up with that!
CM I've seen you mention 4 stroke before , I need to know exactly what do you mean?
Enthusiast
Ď58 VBA Ď79CT90
Joined: 25 Dec 2019
Posts: 53
Location: Chico CA
Sat Sep 19, 2020 2:01 pm quote
Yes please, not exactly sure what four stroking is or what it sounds like.
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Sat Sep 19, 2020 4:59 pm quote
Four stroking is where the carb is so rich that it doesn't fire every cycle.

this video demonstrates what it sounds like pretty well.
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2295

Sun Sep 20, 2020 7:43 am quote
Thanks Chandler, that video explained it completely.
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Wed Sep 23, 2020 1:40 pm quote
So with my move coming up fast, I was out riding the other night getting the engine good n' warm for some carb adjusting, just like my mom SoCal reminded me , but noticed it seemed to be riding like crap. Got home,checked tires thinking one might be low, and instead found about 6mm of front-to-back play in the lower fork bearing.

So given that I definitely won't have time to deal with that in the next two weeks, this project is going on hold until most likely December or January, when I should have time and a workshop to tear into it again.

Back to Scooter Jail for the VBB
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1979
Location: california
Wed Sep 23, 2020 1:50 pm quote
Chandlerman - that leaves us with less to read over coffee in the morning.
How rude!
🙂

Good thing the forum is here when you restart - so you have some clue about what jets you had just tried before meltdown.
You can judge your new neighbors - as they will judge you - by any of them noting that the prior jet exhaust note sounded a little more BaWAAAA! than bAwaaaa!

The kind of neighbors we all hope for - but we don't get to choose em.
-The other CM
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Wed Sep 23, 2020 1:56 pm quote
Hah! I'm definitely going to have the Sprint with me in corporate housing, and may try to sneak the VBB in as well. This will be driven in part by what I think I can get away with on the Domestic Harmony front, but since I don't plan to pack enough tools to drop and repair that front fork, it's probably a bit moot.

I need to capture my jetting notes here, too, as you note. They're on a whiteboard out in the garage at the moment, along with a reminder that I need a 128 MJ because I kind've feel that might have been the right one, if only I had it.
Ossessionato
1963 VBB2T
Joined: 07 Nov 2012
Posts: 2295

Wed Sep 23, 2020 4:02 pm quote
I always said its not a race but the journey that matters.
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Wed Sep 23, 2020 4:10 pm quote
Lynnb wrote:
I always said its not a race but the journey that matters.
and for me, at this moment, it's the bearing race

Seriously, yes. It'd be a lot more frustrating if I didn't have other scoots to ride, but I also can't believe how long what was supposed to be a pretty simply rebuild has dragged out after one low-likelihood event after another.
Molto Verboso
79 P200E, 62 Allstate, 2008 Stella
Joined: 11 Jan 2006
Posts: 1946
Location: Florence, OR
Wed Sep 23, 2020 4:23 pm quote
chandlerman wrote:
It'd be a lot more frustrating if I didn't have other scoots to ride, but I also can't believe how long what was supposed to be a pretty simply rebuild has dragged out after one low-likelihood event after another.
This is exactly why I haven't cracked the cases on B-62 yet. I'll wait till the rain is dumpin, then open er up. So if it takes a month (or two, gasp), I won't wig out.

Safe travels CM1

And you know we're all gonna be expecting to see pics of your ride around Memphis...I mean Nashville.

Last edited by qascooter on Wed Sep 23, 2020 5:01 pm; edited 1 time in total
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Wed Sep 23, 2020 4:40 pm quote
Nashville, but absolutely
Molto Verboso
79 P200E, 62 Allstate, 2008 Stella
Joined: 11 Jan 2006
Posts: 1946
Location: Florence, OR
Wed Sep 23, 2020 5:01 pm quote
chandlerman wrote:
Nashville, but absolutely
Dooohhh! I pay so much attention....
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Sun Jan 03, 2021 3:07 pm quote
So today, I FINALLY got back out into the new workshop and didn't a little time on the VBB. I dropped the front fork and discovered that whatever idiot installed the new front fork (yeah, that'd be me) hadn't gotten them lower bearing race fully seated, hence the play. So I fixed that, then rode around a little bit to warm it up, and finally did a little carb tuning.

I was at a 120/BE1/125 to start, and wound up at a 120/BE3/120. It revs well, but lacks power in the mid- to 3/4 throttle. There's a hill on my street that forced me to drop from 4th to 3rd, and while it's pretty steep, neither the sprint nor stella have any problems with it.

I need to get a 122 main and try that (because I can't find mine), and may advance the timing a degree to see if that gets me a little more grunt. If not, I'll have to look at lowering the port timings, when though they looked good on paper.

It's not as strong a runner as I'd hoped, but that may just be that I'm spoiled by overpowered motors in my other bikes.

And I still have the stella motor I converted to 8" to play with, too
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1979
Location: california
Sun Jan 03, 2021 6:46 pm quote
CM - walk us back a step and remind the current specs?
Combination of lazy and poor memory clouds the mind.
Tru - there can be a tipping point on cylinder lift with just a tiniest amount of base gasket thickness - but curious where peak is right now.
Of course - my first move would have been to look for my 118... but everyone's got their own style.
🙂

Also - what's the exhaust?
Jet Eye Master
PX221 Malossi, O tuned PX200 and some motorbikes
Joined: 14 Jun 2017
Posts: 2575
Location: London UK
Mon Jan 04, 2021 12:15 am quote
Did you ever try a BE4 or BE5? I suspect one of these is correct one for this set up.
Ossessionato
76 Sprint V, 63 GL, 62 VBB, 05 Stella
Joined: 16 Jun 2011
Posts: 2974
Location: Nashville
Mon Jan 04, 2021 6:13 am quote
It's been long enough that I don't recall if I started a BE4 or 5 yet. I have both and will give those a shot next time I get to the garage.

I'll probably advance the timing a degree, too, and see where that leaves me. One nice thing about the SI carbs is how easy it is to adjust the jetting. I'm used to my PWK where it's a major operation to make any change.

CM, I have a SIP Road XL on it right now and may swap back to a SIP Road 2.0 for ground clearance, but I'd like to get the carb dialed in as-is first, so I have a baseline to compare the swap to.

On the bright side, it's definitely ride-able as-is, it just drags a little on the uphill.
Molto Verboso
62 VBB1T Round Tail W/ leaner sidecar
Joined: 26 Jan 2019
Posts: 1979
Location: california
Mon Jan 04, 2021 8:47 am quote
Sounds good - both figuratively and literally Im sure.
I had good luck adding some grunt by moving to the Polini box from Road II.
Was one of my more affordable upgrades.
Playing with exhaust seems wise - and a bit more ground clearance is always nice.
Will be interested to see how it behaves with jetting and Road II comparison.
Sounds like you have your new test spot with the hill.
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