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Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Wed Aug 20, 2014 7:25 pm quote
Cool! Take a Gazillion photos. No more, no less.
Hooked
1968 Sprint 175, Lambretta Li185S
Joined: 11 Jan 2012
Posts: 289
Location: London
Wed Aug 20, 2014 11:16 pm quote
chandlerman wrote:
Well, I figured WTF and just dropped the $150, including shipping. I figure it'll be easier to figure out the basics of fitting it with the motor out of the bike.

I know that I'm solidly into "Too much is never enough" mode, but sometimes I just can't help myself.
Sweet!

I really like the PWK carb and mine is pretty crisp now and I have a bigger Polini version on order.

On that 50cc reed it looks like your adapter plate wont have too mch to do. You just need to keep it thin so the carb isn't too high. The float wan'ts to be as low as possible.

Be good to hear how you get on.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Aug 21, 2014 2:37 am quote
Ginch wrote:
Cool! Take a Gazillion photos. No more, no less.
Ginch, you know full well that I love nothing more than posting up loads of project photos with full annotations of work plans and everything else.

It's how I tap the collective wisdom of this crowd as well as capture it for my and others' future reference.

Besides, I can't wait to see what I wind up doing to make that adapter plate, either. Already designing it in my mind. It may not be all that pretty, but it'll get the fuel & air where it needs to go and be fab-able with nothing but a dremel, files and taps.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Thu Aug 21, 2014 2:48 am quote
Photos are god's gift to the sighted! Thanks Chandlerman!

I just hope it's not too hard to get that carb in the right spot. Fingers crossed.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Aug 25, 2014 6:34 pm quote
mmmmm....30mm PWK....
So I got home from work this evening and I had a package...the 30mm PWK carb, all the way from Taiwan. I ordered it late Thursday night and it's already here, free shipping and all:


I wasn't sure how well it would do even trying to fit without fabbing up some sort of mating block. So you can imagine my surprise when I saw how close it was. I put the gasket on and it looked pretty close:


Even better, the bolts matched the airbox mounting holes:


I built a small template out of card stock and determined that, yes, this *could* work. All I would need to do would be get medieval on that reed block with my Dremel.

Now normally, I'm hesitant to do destructive things, but this is not a finely machined piece of work. It's cheaply cast out of punk metal, so I figured I'd try to get close enough to at least prototype this bad boy.





I had to widen out the two holes for the carb studs to get them to fit. Once I did that, I could work on the alignment. I went to work on the right/front stud hole (yeah, that sounds dirty--and if it didn't before, it probably does now), taking metal off until I could get the bolts in place.

And it was going swimmingly, until...


Fortunately, I'm well past my fear of breaking things at this point in the project. The area I removed is all overhang into the air anyway.


Leading ultimately to


I don't know why the carb looks so huge in that picture. It's big, but not that big.

Now, there's one problem, and that's the airflow down into the case. It's pointed toward the clutch, rather than down the ramp into the crank:


I could flip it around except for two things. First, I don't think the carb will fit on the engine once it's in the case. Second, I don't want to blow away the other carb stud hole.

But if I did, it would basically look like this:


So what I have now is not really long-term workable--this configuration will only work with the cowling off, and the intake clearly needs to be reversed for proper flow.

But I got it on there without doing anything that will impact my ability to revert back to the LML reed block and an si carb should I so choose.

Now, I'm just waiting for the box from Hodgespeed to arrive. According to UPS, it'll be here on Friday, so barring a disaster, I should have everything I need to have this bad boy back together over the weekend.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Mon Aug 25, 2014 7:06 pm quote
Awesome photos Chandlerman. Yes it was quick postage but you didn't waste much time either!

How about a triangular block that goes under the reed block and straightens the direction of flow? Would that lift it too high? You could make something from a block of wood to test the concept.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Aug 25, 2014 7:11 pm quote
Ginch wrote:
Awesome photos Chandlerman. Yes it was quick postage but you didn't waste much time either!

How about a triangular block that goes under the reed block and straightens the direction of flow? Would that lift it too high? You could make something from a block of wood to test the concept.
That was what I was originally thinking. I figured I could do it with a couple of thin aluminum plates and fill between them with jbweld to complete it. I may still have to go that route, depending on whether or not I have adequate clearance once it's back in the frame, but this will be a start.

Ultimately, if I feel like this beast makes a difference in performance, I'll probably just spend the cash and buy decent mounting hardware so it'll both have proper airflow and fit inside the cowling.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Tue Aug 26, 2014 7:06 pm quote
Good News and Bad News today.

The Good News is that the reed block that I bought off Vader arrived today.


The Bad News is that I realized that I would have to flip the cheap-ass mounting that came with the carb around after all. I forgot about the flywheel. Doh.

So I flipped it around and I seriously doubt that it'll clear the frame.

Assuming it does, though, I'll have to get a small piece of aluminum stock and fab up a cover plate because once I flipped it around, the reed block didn't cover the opening in the cases:


As it is, I still don't think it'll go on until I get some reeds to fit the Vader block.

For now, the 30mm carb is going on hold at least until I fit the cases back in the bike and can decide if there's any point in trying to fit the carb with the cheap-o blocks.

I'll finish the rebuild with my pimped out LML reed block and 24/24si carb and go from there.

Never a dull moment!
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Tue Aug 26, 2014 7:54 pm quote
Can you please take a picture of the two reed blocks side by side if it's no trouble? And perhaps one of each looking down through them into the case? Maybe the cheapo could be propped up to simulate the position with the linking bit in place? Be nice to see the actual difference.
The MMW looks huge sitting there, I wonder if they couldn't take advantage of the LML opening and drop it it in a little?
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Wed Aug 27, 2014 6:56 pm quote
Ginch, I like to think I'm nothing if not service-oriented.

Here's front, top and side views of the MMW block:





Oh, and this, which will not be dealt with as easily on the MMW as it was on the random crap metal:


Here's some more fit shots of the cheap-o block and mount, too.

Down the mouth with it sitting flat:


And the estimate of what the fit probably needs to make it work.



And, finally, for scale, here's the stock airbox as compared:



How I might deal with that will be an adventure for another day, but will not be a permanent solution in any way, shape or form.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Wed Aug 27, 2014 7:24 pm quote
Thanks Chandlerman, great stuff!!

With the cheapo at the estimated height, does the carb end up in about the same position as the MMW? Or higher/lower? Forward/back? At least it seems to be pointing roughly in the right direction from the pictures.
Hooked
1968 Sprint 175, Lambretta Li185S
Joined: 11 Jan 2012
Posts: 289
Location: London
Thu Aug 28, 2014 2:17 am quote
Mate, thanks for this investigation. It looks like there might be a 50cc reed out there but not this one. It's angled so it's either wrong or won't fit on the bike and machining a good adapter up gets you close to the cost of a proper job.

The other reed box looks really good. I'm going for the MRP one next month to strap my 30 PWK to.

Cheers.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Aug 28, 2014 6:32 pm quote
blake7even wrote:
Mate, thanks for this investigation. It looks like there might be a 50cc reed out there but not this one. It's angled so it's either wrong or won't fit on the bike and machining a good adapter up gets you close to the cost of a proper job.

The other reed box looks really good. I'm going for the MRP one next month to strap my 30 PWK to.

Cheers.
I won't really know for sure until I stick the motor in the bike and see what I can do, but for right now, I'm thinking that I'll most likely just run with my heavily modded LML reed and a 24/24si to start.

I might hack together something horrible involving a couple aluminum plates and JB weld between them to fill in the sides, but I don't have a throttle cable for the PWK so I may wait to do anything until I get around to ordering the reed block for the MMW along with sorting out or ordering a new throttle cable and choke conversion.

Just what my wife wants to see...more scooter parts.

Maybe I'll have them shipped to work...
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Oct 23, 2014 1:57 pm quote
As noted here, I replaced my CDI today and that turns out to have been the source of my tuning problems.

This thing now hauls some serious ass, rev's to about 9,000 RPM's in 1st & second.

It's got the 21 tooth clutch in it and I've still got to get it properly jetted, but over all, it's well on its way to being a serious screamer, and that's just with the 24/24si carb and my heavily modified LML reed block.

Porting 101 For the Win!
Ossessionato
1976 Super (x 2), 1974 Primavera (x 2), 2006 Fly 150
Joined: 26 Sep 2013
Posts: 4906
Location: So Cal
Thu Oct 23, 2014 2:57 pm quote
Congrats man, nice to hear it all came together.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Oct 23, 2014 3:14 pm quote
Just validated my measured top speeds against http://gearingcalc.free.fr/. It confirms that I'm getting 9,000 RPM's at the top end, with loads of tuning still to do.

I did not expect that, but I'm thoroughly stoked about it.
Addicted
69 VLB, 79 P200, P125/Stella and a couple frames
Joined: 06 Jul 2012
Posts: 909
Location: Alabama
Thu Oct 23, 2014 4:44 pm quote
What kind of jetting are you using. I've been browsing at similar set ups to kind of help give me a starting point for mine. I'm ported more aggressively, but I can get a no less than for sure.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Oct 23, 2014 5:55 pm quote
panchoboots wrote:
What kind of jetting are you using. I've been browsing at similar set ups to kind of help give me a starting point for mine. I'm ported more aggressively, but I can get a no less than for sure.
55/160 idle jet
160-BE3 and either a 125 or 127 main in a 24/24 si carb.

The 30mm is still on the shelf. I need to get some reeds for the MMR manifold I scored off Vader.
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05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Oct 23, 2014 6:10 pm quote
More for my own future reference than anything, a link to my Clutch and Gearing Thread, which was much harder to search out than this one, for tooth counts:
chandlerman wrote:
Looking at the gearing, it counts out tooth-wise the same as a P200E:
Spring Gear, main gear 68t and gearing of:
1st -- 12t
2nd -- 13t
3rd -- 17t
4th -- 21t
Gears:
1st -- 57t
2nd -- 42t
3rd -- 38t
4th -- 35t
with a 21-tooth clutch.
Except that I wound up going with a 65 tooth main.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Thu Oct 23, 2014 6:12 pm quote
Sounds great Chandlerman! Well done.

What crank did you end up with? It'll be interesting to see how the LML reed holds up to those rpms.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Thu Oct 23, 2014 6:31 pm quote
Ginch wrote:
Sounds great Chandlerman! Well done.

What crank did you end up with? It'll be interesting to see how the LML reed holds up to those rpms.
I wound up with a Worb5 flowed crank. Rob Hodge recommended it.

The reed is not the steel LML reed, it's a .45mm Polini carbon fibre reed that I'd put in before I blew the motor up the first time.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Thu Oct 23, 2014 10:48 pm quote
I have that one in my LML case too. Haven't ridden with that motor for over a year.
Molto Verboso
Vespa GS150, Messerschmitt GS150
Joined: 21 Jan 2013
Posts: 1060
Location: Glasgow
Fri Oct 24, 2014 2:28 am quote
Re: mmmmm....30mm PWK....
chandlerman wrote:
So I got home from work this evening and I had a package...the 30mm PWK carb, all the way from Taiwan. I ordered it late Thursday night and it's already here, free shipping and all:


I wasn't sure how well it would do even trying to fit without fabbing up some sort of mating block. So you can imagine my surprise when I saw how close it was. I put the gasket on and it looked pretty close:


Even better, the bolts matched the airbox mounting holes:


I built a small template out of card stock and determined that, yes, this *could* work. All I would need to do would be get medieval on that reed block with my Dremel.

Now normally, I'm hesitant to do destructive things, but this is not a finely machined piece of work. It's cheaply cast out of punk metal, so I figured I'd try to get close enough to at least prototype this bad boy.





I had to widen out the two holes for the carb studs to get them to fit. Once I did that, I could work on the alignment. I went to work on the right/front stud hole (yeah, that sounds dirty--and if it didn't before, it probably does now), taking metal off until I could get the bolts in place.

And it was going swimmingly, until...


Fortunately, I'm well past my fear of breaking things at this point in the project. The area I removed is all overhang into the air anyway.


Leading ultimately to


I don't know why the carb looks so huge in that picture. It's big, but not that big.

Now, there's one problem, and that's the airflow down into the case. It's pointed toward the clutch, rather than down the ramp into the crank:


I could flip it around except for two things. First, I don't think the carb will fit on the engine once it's in the case. Second, I don't want to blow away the other carb stud hole.

But if I did, it would basically look like this:


So what I have now is not really long-term workable--this configuration will only work with the cowling off, and the intake clearly needs to be reversed for proper flow.

But I got it on there without doing anything that will impact my ability to revert back to the LML reed block and an si carb should I so choose.

Now, I'm just waiting for the box from Hodgespeed to arrive. According to UPS, it'll be here on Friday, so barring a disaster, I should have everything I need to have this bad boy back together over the weekend.
Why didn't you remove the carburettor studs and replace them with M7 bolts or just cut them.

My engine is ported to the Polini 180 top end and Im using the MRP manifold, if you look at the top section of the manifold it allows you movement on the position of the carb which can work in your favour if you are struggling for space. The other think you can do is cut or grind the casing away on the flywheel side. I would also change air filter, with this filter the chrome face stops the air going directly into the carb, I would use the Ram Air Filter, might not look as good but works better.
IMG_3048 by GLscoot, on Flickr
Not the best picture, but if you look closely you can see where I have cut/grind a section of the flywheel section on the casing.

Picture of Ram air filter.
Vespa GS by GLscoot, on Flickr
Gary
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Sat Oct 25, 2014 9:03 am quote
That's a damn nice looking ride

I've got the MMW block, just need to get the reeds for it and then I'll be off to the races.

I did some test fitting before I rebuilt the motor and other than removing that rear carb stud, don't anticipate any real challenges with the install besides learning to jet a PWK carb.

I also checked squish this morning because compression was only 120PSI and it was 3mm, so now I need to get the head shaved down a little. Meh.

I almost hate to do it, though, because inspection of the head-cylinder joint showed no leakage whatsoever. Oh, well...
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Tue Nov 11, 2014 6:45 pm quote
A few notes for posterity on my current setup, which is what I'll probably run until things warm up and I switch to the 30mm PHBH.

I shaved down an old DR head since the new one has been beautifully leak-free and squish is now just over 2mm and compression is at 140psi. I think I can live with that for the time being.

The jetting is 55/160 idle and a 160-BE3-122 main. I'm going to try a 125 main, though, as when I had it out on the highway, heat was up to 350f on the CHT and that was starting to make me nervous.

Around town, it screams, especially once it gets up into the power band. Other than starting off the line, power transfers are nice and clean from one gear to the next.

Timing is 18 degrees BTDC, so I'm going to try retarding the timing to 17 degrees BTDC and see if that gets me a little more low-RPM power, too.

Out on the highway, it accelerates steadily. The fastest I've had it was 68 mph on GPS and it was still accelerating despite a bit of a headwind. At that point, I was closing fast on the car in front of me, feeling past the point of comfort with the stock suspension, and coming up on the exit I wanted to take, so finding the true top speed will have to wait another day.

Checking 68 MPH against the gearing calculator, though, I was running about 7,000 RPM's in 4th at that speed, so I will almost certainly get to the end of the power band by 75mph, tops. This is with a 21 tooth clutch. I've got a 22-tooth, but it's got a warped plate or something, so it's on the shelf for the time being.

Still, I originally told myself I would be happy with a bike that could cruise at 70, so I'll take it, even if this now means it's time to start thinking about aluminum rims with tubeless tires and new shocks and springs.

At some point, I'll probably fix the speedo, but it's hard to get motivated to do stuff like that now that the temperature has plunged for the winter.
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05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
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Location: Chicago. Well, Evanston, but that's almost Chicago
Tue Nov 11, 2014 6:50 pm quote
Oh, yeah...gearing calc's. I don't expect I'll ever see 85 MPH/136 KmH, nor would I want to.

Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Sun Feb 01, 2015 6:10 am quote
I've continued to wrestle with heat levels at highway speeds for a while.

Ultimately, I decided that the planed head was just not working for me and I've gone back to the stock head with its slightly excessive squish and only ~125 psi of cold compression.

I changed the timing to 17 degrees and I'd been playing with the jetting for a while, as temps were still getting up to 375 and climbing out on the highway.

Yesterday, inspecting the cylinder, I saw an oil drip from the cylinder head so I checked the torque and two of the head bolts were seriously loose, about 3/4 of a turn and a third was about 1/4 turn loose. The only one that wasn't loose was the top right, which is effectively double-nutted by the cooling shroud holding bolt.

That being fixed, I took it out for a ride and it was a little boggy, but I could still feel a definite improvement in torque when it got up onto the pipe. Took it out on the highway for a bit and while I wasn't able to really test it due to traffic, I was cruising happily at 60-65 mph with a max of only 330f on the CHT.

I upjetted to a 125 main a couple weeks ago to try and address the high temp's at highway speed, but it felt pretty boggy around town, so assuming that was the head bolts, I'll now take it back down to a 124 or 122 and probably be able to declare the carb tuning done until I put the 30mm on it.

Now for the suspension, because while it's pretty comfortable up to about 62mph, it also feels like there's no margin for error or unexpected events and that's just not a good place to be.
Molto Verboso
Vespa GS150, Messerschmitt GS150
Joined: 21 Jan 2013
Posts: 1060
Location: Glasgow
Sun Feb 01, 2015 10:42 am quote
I don't think you need the 30mm carb on there, 26mm should be fine. My scooter is the same at lower speed, very boggy. What filter did you decide on and do you have a lot of spit back.

You will be doing well to hit 75mph, I've had it at 70 and had to back off. Fuel & Oil% are you using, its recommended that you go up to 3% instead of the standard 2%
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Sun Feb 01, 2015 12:31 pm quote
I would have thought the bigger carb had the potential to create more bogging too. But it sounds like it's going nicely.
GLscoot wrote:
... its recommended that you go up to 3% instead of the standard 2%
Why is that Gary?
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05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Sun Feb 01, 2015 12:49 pm quote
I'm still running a 24/24si carb with the modified LML reed block. It's boggy because I was trying to paper over the overheating issue with a richer main jet.

I picked up the 30mm carb on a drunken whim but haven't installed it yet.

I've got an MMW block but still need to get some RD350 reeds for it before I install it. If I go for a smaller carb (which is probably the correct move), then I'm looking at a few hundred bucks to get into the side draft carb business.

I found that low-end and mid-range performance on my VBB was significantly improved by swapping from the 24/24 to a 20/20, but that's with a pretty restrictive pipe and no porting. Same principle applies, though.

In the meantime, I'm thinking that replacing the ten-year-old LML stock shocks and going tubeless on my rims might be a better use of cash since this thing will already run faster than the suspension can handle.

If I ditch my spare and go with the Pinasco split aluminum rims, I'm taking 30 lbs of weight off the bike, most of it unsprung. If I pulled all the tools out of the glovebox, that's probably another 10 pounds of weight gone, or 40 lbs total, which wouldn't be a bad thing either.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Sun Feb 01, 2015 12:57 pm quote
chandlerman wrote:
If I pulled all the tools out of the glovebox, that's probably another 10 pounds of weight gone, or 40 lbs total, which wouldn't be a bad thing either.
When I've loaded up the front rack before, I found I really like the way it feels... much more "planted" or something. So I would say yes to the wheels but not be in a hurry to empty the glovebox!
Molto Verboso
Vespa GS150, Messerschmitt GS150
Joined: 21 Jan 2013
Posts: 1060
Location: Glasgow
Mon Feb 02, 2015 3:06 am quote
Ginch wrote:
I would have thought the bigger carb had the potential to create more bogging too. But it sounds like it's going nicely.
GLscoot wrote:
... its recommended that you go up to 3% instead of the standard 2%
Why is that Gary?
Iam not the best to answer that, but the shop that ported my casings said it would be best to run 3% rather than the 2%. I am actually running 2.5% and still think that is to much. Hopefully someone on here will give me a better explanation as to running 3%.
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05 Stella, '62 VBB, 76 Sprint V, 63 GL
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Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Feb 02, 2015 5:07 am quote
GLscoot wrote:
Ginch wrote:
I would have thought the bigger carb had the potential to create more bogging too. But it sounds like it's going nicely.
GLscoot wrote:
... its recommended that you go up to 3% instead of the standard 2%
Why is that Gary?
Iam not the best to answer that, but the shop that ported my casings said it would be best to run 3% rather than the 2%. I am actually running 2.5% and still think that is to much. Hopefully someone on here will give me a better explanation as to running 3%.
Running 3% (allegedly) helps to provide more lubrication to the bearing & piston when running at WOT for extended periods of time. If you're not doing a lot of that, then I think it mostly just seems to increase the risk of a fouled plug.

As I noted in another thread recently, I used to have a 2-stroke outboard that called for 4% oil during periods of "extended use," i.e. WOT.
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05 Stella, '62 VBB, 76 Sprint V, 63 GL
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Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Feb 02, 2015 5:15 am quote
Ginch wrote:
chandlerman wrote:
If I pulled all the tools out of the glovebox, that's probably another 10 pounds of weight gone, or 40 lbs total, which wouldn't be a bad thing either.
When I've loaded up the front rack before, I found I really like the way it feels... much more "planted" or something. So I would say yes to the wheels but not be in a hurry to empty the glovebox!
Other than the 18" of snow on the ground this morning, I'd get right on testing that
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1976 Super (x 2), 1974 Primavera (x 2), 2006 Fly 150
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Posts: 4906
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Mon Feb 02, 2015 8:35 am quote
We've noticed some weight in the cowl glovebox actually makes our scoot handle better... it counter balances the lopsided engine weight.
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05 Stella, '62 VBB, 76 Sprint V, 63 GL
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Mon Feb 02, 2015 9:54 am quote
SoCalGuy wrote:
We've noticed some weight in the cowl glovebox actually makes our scoot handle better... it counter balances the lopsided engine weight.
I shift the 10 lbs of tools between the Stella and the VBB, but I think maybe I'm so used to the lopsided motors that I can't tell the difference any more.

I'll be curious to see if I can feel a difference pulling the tools out of the glovebox on the Stella. I know I feel a definite difference in the front end when I put a bunch of crap on the rear rack.
Molto Verboso
Vespa GS150, Messerschmitt GS150
Joined: 21 Jan 2013
Posts: 1060
Location: Glasgow
Mon Feb 02, 2015 10:46 am quote
chandlerman
you are probably correct with the 3% fouling the plug if you are pottering about town, I've been changing my plug every month as at the moment Im using the scooter for work and I have to stop every 100yds. Im going back to 2% from now on, and will add an extra % when I go for runs. I know i have still some work to do on the carb set up.
Im using pre-mix fuel so should be easy enough to control.
Mr. Clean
P,SUPER,V90, 50 Special
Joined: 27 Jul 2010
Posts: 10207
Location: This is't my locker!
Mon Feb 02, 2015 11:20 am quote
vespa, even highly tuned = %2 Motul 710 *Never fails

*at least for me
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2268
Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Feb 02, 2015 11:30 am quote
Vader19 wrote:
vespa, even highly tuned = %2 Motul 710 *Never fails

*at least for me
Motul 710 can never fail, it can only Be Failed .

I run Motul at 2% myself and have been fine for the past four or five years with it in both the VBB and the Stella.
Veni, Vidi, Posti
74 Super, 75 Super, PX project, LML off-roader and new to 2018, '66 Blue Badge Smallframe
Joined: 30 Nov 2011
Posts: 7121
Location: Victoria, Australia
Mon Feb 02, 2015 1:20 pm quote
If I wanted to run 3% (which I don't), I would upjet a couple of points to compensate - ie more petrol (gas to you guys!) to offset the oil... pretty sure Piaggio downjetted when they introduced autolube.
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