[Voodoo?] Carb Jets

[Kaos]

So I've run into a little bit of an issue in my quest for Voodoo.
I've just installed a new head on my Bud and its seriously increased the airflow. The issue I'm running into is that my old jet was already at a 115, and the largest you can get at scooterworks is a 130. I've drilled out a jet to 135 and its just to the point of actually running. I can't find anywhere to get a jet any bigger than a 130 so far, and can't find a drill bit in between 135 and 160 so I figured I'd ask:

Anyone running anything bigger than a 130 main, or know where to find one?

[Lostmycage]

Not for the Buddy carb. For some reason the jet part numbers are listed as the idle circuit jets for other model Keihin carbs. It's not quite a "real" Keihin, but it's very closely based on one. Also, the PGO carbs differ from the China GY6 engines at the carb since most of them seem to use Mikuni jets. <a href="topic10679.html#136712">See some similar sleuth-work from the Blur forums</a>.

So the head was causing that much of a flow disruption to make the "stockish" mix that much leaner that with the new head? That's rather alarming.

Second spin on it... are you sure there's no leaks caused by slight imperfections in the machined surfaces or possibly in combination with used (precompressed and memorized) gaskets? Just trying to cover the bases so if nothing else, they're eliminated.

If you want to go nut-so-crazy, I have a flat slide that fits the same as the stock carb that I never got around to trying out. It's jets go up to 200 or so, lol.

[Kaos]

Not for the Buddy carb. For some reason the jet part numbers are listed as the idle circuit jets for other model Keihin carbs. It's not quite a "real" Keihin, but it's very closely based on one. Also, the PGO carbs differ from the China GY6 engines at the carb since most of them seem to use Mikuni jets. <a href="topic10679.html#136712">See some similar sleuth-work from the Blur forums</a>.

So the head was causing that much of a flow disruption to make the "stockish" mix that much leaner that with the new head? That's rather alarming.

Second spin on it... are you sure there's no leaks caused by slight imperfections in the machined surfaces or possibly in combination with used (precompressed and memorized) gaskets? Just trying to cover the bases so if nothing else, they're eliminated.

If you want to go nut-so-crazy, I have a flat slide that fits the same as the stock carb that I never got around to trying out. It's jets go up to 200 or so, lol.

Hmm, mine has the Keihin logo right on the side, so I figure it *IS* a Keihin.

I'm very sure that its not leaking, I've checked everything multiple times.
And this head is WORKED. Its got hugely oversized valves, a very smooth port and polish, and a 2mm shave. I'll have a review of it when I'm done but its been impressive so far.

I also drilled a jet to 160(next bit size I had) and it ran without anything that would indicate a leak, but was far to rich and was bogging.

How much you want for the flat-slide?

[Lostmycage]

Lol, you went from 120 (the largest available unmodded) to 160 and you're noting it's rich!? Damn man. That's what the kids call overkill, hehehe.

Something sounds off, but it's a bit on the late side for my brain to work the details just right. Shoot me some PM's in the morning and we'll see if we can find the gremlins.

[ScooterTrash]

Lol, you went from 120 (the largest available unmodded) to 160 and you're noting it's rich!? Damn man. That's what the kids call overkill, hehehe.

Something sounds off, but it's a bit on the late side for my brain to work the details just right. Shoot me some PM's in the morning and we'll see if we can find the gremlins.

He went from 135 to 160

Kaos You should do a compression test and possibly pressure test the carb to the head just to be sure. I'm only running a 110 but I dont have an open filter, just my drill mod. What head are you running? We'll have to compare after I do mine

[Kaos]

Lol, you went from 120 (the largest available unmodded) to 160 and you're noting it's rich!? Damn man. That's what the kids call overkill, hehehe.

Something sounds off, but it's a bit on the late side for my brain to work the details just right. Shoot me some PM's in the morning and we'll see if we can find the gremlins.

He went from 135 to 160

Kaos You should do a compression test and possibly pressure test the carb to the head just to be sure. I'm only running a 110 but I dont have an open filter, just my drill mod. What head are you running? We'll have to compare after I do mine

I can't tell you till I'm done reviewing it, but its seriously worked over.

The company producing it claims that you need a 150 jet on a STOCK scooter with this head and an open filter. I'm not sure I'll end up that high, but we'll find out.

Compression test is on the agenda.

I disconnected the wire to the carb's enrichener to keep the mixture richer and with the 135 jet its actually running quite well. I've not done a plug cut yet to see how the mixture is but its idling smoothly and not popping at all on deceleration anymore. Its also got quite a huge increase in power. I'd say this made more difference than my bigbore did at this point, though I've only run it up and down the block as a test.

I'll be riding it to work today, so I'll update everyone after I get to the office.

[Lostmycage]

It requires a 150 jet and an open air filter. Wow, that's pretty serious.

Does the company say what type of jet they're referring to? A lot of what I found when I was researching carbs pointed to many of the Chinese scoots (the majority of GY6 clones and probably what the head you've got is intended for) using a Mikuni knock-off. I thought I found a cross-reference for jet sizes a while back, but I don't remember where I put them.

Something sounds vaguely familiar about that head... It's a 2 valve, right?

[Kaos]

It requires a 150 jet and an open air filter. Wow, that's pretty serious.

Does the company say what type of jet they're referring to? A lot of what I found when I was researching carbs pointed to many of the Chinese scoots (the majority of GY6 clones and probably what the head you've got is intended for) using a Mikuni knock-off. I thought I found a cross-reference for jet sizes a while back, but I don't remember where I put them.

Something sounds vaguely familiar about that head... It's a 2 valve, right?

The main jet, they tested it with a different Keihin carb that fits larger jets.
The company that I'm testing it for was kind enough to send me one of those carbs, but the throttle butterfly is farther forward than the stock carb, so my throttle cable is too short

Yep, its a 2-valve, though the valves are HUGE, 30mm/25mm!

[Lostmycage]

Interesting. I thought there was a fair amount of play in the cable length. Why not just get a longer cable to go with the test carb? All the time and effort to put on a new head and carb... what's another 15 minutes to thread a cable?

What model carb did they send you that has the same dimensions as the stock carb? That could be a heck of an upgrade in it's own right.

A good properly worked head is like the missing link for real performance. I kept saying that I was going to do that on the Blur... but I didn't want the downtime without a bike... then I didn't want to risk screwing up the one I had, lol. Procrastination is a bitch!


That head does sound familiar. The place that sent it to you isn't in your neck of the woods, is it?

[djelliott]

Sounds like someone needs a bigger carb.

[Kaos]

Interesting. I thought there was a fair amount of play in the cable length. Why not just get a longer cable to go with the test carb? All the time and effort to put on a new head and carb... what's another 15 minutes to thread a cable?

What model carb did they send you that has the same dimensions as the stock carb? That could be a heck of an upgrade in it's own right.

A good properly worked head is like the missing link for real performance. I kept saying that I was going to do that on the Blur... but I didn't want the downtime without a bike... then I didn't want to risk screwing up the one I had, lol. Procrastination is a bitch!


That head does sound familiar. The place that sent it to you isn't in your neck of the woods, is it?

The issue isn't threading the cable, its getting the cable to thread in

I'll have to look at the model when I get home, it was a Keihin clone but appeared to be a high quality one.

I rode it to work and its still running lean, but MAN its got power. I was doing 50, and changed lanes to pass a car. I gunned it and wheelied at 50! Scared the poo right outa me, but man it went!

And the place that sent it to me might just be in my neck of the woods

[Lostmycage]

The issue isn't threading the cable, its getting the cable to thread in

I'll have to look at the model when I get home, it was a Keihin clone but appeared to be a high quality one.

I rode it to work and its still running lean, but MAN its got power. I was doing 50, and changed lanes to pass a car. I gunned it and wheelied at 50! Scared the poo right outa me, but man it went!

And the place that sent it to me might just be in my neck of the woods

A wheelie at 50, you say? This sounds promising.

Does the new carb have the soldered on pin like the stock carb does, or does it attach differently? You might be able to take it off, thread it and re-solder it... maybe.

I think I've definitely (like 85% sure) heard of the place you got it from. I'll keep an eye on this for sure, since I've been curious about the place for a while now.

Go, go missing link!

[Kaos]

The issue isn't threading the cable, its getting the cable to thread in

I'll have to look at the model when I get home, it was a Keihin clone but appeared to be a high quality one.

I rode it to work and its still running lean, but MAN its got power. I was doing 50, and changed lanes to pass a car. I gunned it and wheelied at 50! Scared the poo right outa me, but man it went!

And the place that sent it to me might just be in my neck of the woods

A wheelie at 50, you say? This sounds promising.

Does the new carb have the soldered on pin like the stock carb does, or does it attach differently? You might be able to take it off, thread it and re-solder it... maybe.

I think I've definitely (like 85% sure) heard of the place you got it from. I'll keep an eye on this for sure, since I've been curious about the place for a while now.

Go, go missing link!

Threaded on pin where? Its ALMOST identical to the stock carb. Its a 24mm CVK Keihin knock off. the biggest difference is that the throttle butterfly is farther forward, and it uses larger jets. It also uses a 4 screw float bowl instead of the 3 screw bowl our stock carbs use.

[Lostmycage]

Words are failing me... the thick round pin that goes in the linkage at the carb. Can't that be taken off and pulled through the sleeve, then re-soldered?

It's been a while since I've looked at a Buddy carb, so I might be getting mixed up... especially considering that I could have sworn the bowl has 4 screws... The diaphram has 3 screws... Arrgh! I thought I was done with carbs (lol, yeah right!).

[Kaos]

Words are failing me... the thick round pin that goes in the linkage at the carb. Can't that be taken off and pulled through the sleeve, then re-soldered?

It's been a while since I've looked at a Buddy carb, so I might be getting mixed up... especially considering that I could have sworn the bowl has 4 screws... The diaphram has 3 screws... Arrgh! I thought I was done with carbs (lol, yeah right!).

Hmm, maybe. I'll take a look at it again when I get home. I'd LIKE to be able to use the new carb, as it has jets up to at least 300, which should be far larger than I'll EVER use.

[AZruckuspride]

I hope this helps. http://www.showandgo.com.au/jet/jet.htm ... ~mainFrame These are the jets for Keihin carbs. Ours uses the 99101-393 main jet

http://www.motorcycle-superstore.com/4/ ... 7c64bf1dad

A little expensive, but there you go.

Here's another. http://www.rockymountainatvmc.com/allPr ... lyId=25596

[Kaos]

I hope this helps. http://www.showandgo.com.au/jet/jet.htm ... ~mainFrame These are the jets for Keihin carbs. Ours uses the 99101-393 main jet

http://www.motorcycle-superstore.com/4/ ... 7c64bf1dad

A little expensive, but there you go.

Here's another. http://www.rockymountainatvmc.com/allPr ... lyId=25596

Sweet, two of those three are correct. The motorcycle superstore one looks to be the larger jets.

Thanks!