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Old 10-20-2012, 08:49 AM   #106
oldroadie
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Originally Posted by hardwaregrrl View Post
Yeah, this is the info I was looking for. I had to choke the bings, but not the mikunis so not sure if I should add more air via the screw or get an even smaller pilot jet. I'm afraid going smaller that a 20 is too small and may starve it....I forget if air screw in adds more air or takes it away.?
AFAIK screw out for more air on the Mikuni, just the opposite of the Bing. But really you need the pilot right so the screw setting can be set for best idle mix. Isn't there a 22.5 pilot as well? I'm way too fat now with a 30 so I'm headed to the local Yamaha shop to see what they might have in hand, ideally I'd like a 20, 22.5, and a 25. Once that's right I can start mucking about with the main jet circuit and needle, if I need to.
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Old 10-20-2012, 11:47 AM   #107
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Originally Posted by oldroadie View Post
AFAIK screw out for more air on the Mikuni, just the opposite of the Bing. But really you need the pilot right so the screw setting can be set for best idle mix. Isn't there a 22.5 pilot as well? I'm way too fat now with a 30 so I'm headed to the local Yamaha shop to see what they might have in hand, ideally I'd like a 20, 22.5, and a 25. Once that's right I can start mucking about with the main jet circuit and needle, if I need to.
My 135 mains are batting eyelashes at me. 140 works and 130 did notlet me max speed
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Old 10-23-2012, 08:38 AM   #108
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Update

A really awesome inmate sent me a colotune for the cost of shipping. I tried it out. And apparently my AFR is spot on. I got a nice blue all through the range of rpm, just a bit of a yellow rich tone when the throttle was rolled on abruptly.

I also was able to achieve 37mpg mixed use, 2/3 hwy 1/3 city riding. That's pretty much what I was getting with the bings. 165 main, 35 pilot 2.5 turn out on the screw (thinking about going back to the 20) needle in the middle 5FP17, needle jet 389 P2, standard slide.

I'm still having problems on start up, it won't start on choke. Only after no choke and a bit of throttle, it has done thing from 20 pilots to 45 pilots. bike runs fine at low speeds, don't get it? maybe I need an even smaller pilot?? It also stinks on start up, exhaust smell is very strong. I just checked the valves and timing again, and everything is spot on! So....not sure where I'm at other than the pilot circuit needs attention.
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Old 10-23-2012, 08:49 AM   #109
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Originally Posted by hardwaregrrl View Post
Update

A really awesome inmate sent me a colotune for the cost of shipping. I tried it out. And apparently my AFR is spot on. I got a nice blue all through the range of rpm, just a bit of a yellow rich tone when the throttle was rolled on abruptly.

I also was able to achieve 37mpg mixed use, 2/3 hwy 1/3 city riding. That's pretty much what I was getting with the bings. 165 main, 35 pilot 2.5 turn out on the screw (thinking about going back to the 20) needle in the middle 5FP17, needle jet 389 P2, standard slide.

I'm still having problems on start up, it won't start on choke. Only after no choke and a bit of throttle, it has done thing from 20 pilots to 45 pilots. bike runs fine at low speeds, don't get it? maybe I need an even smaller pilot?? It also stinks on start up, exhaust smell is very strong. I just checked the valves and timing again, and everything is spot on! So....not sure where I'm at other than the pilot circuit needs attention.
Well,

Sounds like you're Rich at start for starters

Are you sure your chokes are off at start?

Were you able to ride the bike and observe the colortune at the same time?
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Old 10-23-2012, 08:59 AM   #110
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Originally Posted by Les_Garten View Post
Well,

Sounds like you're Rich at start for starters

Are you sure your chokes are off at start?

Were you able to ride the bike and observe the colortune at the same time?
No....too scared to do that.....might try to at least put it on the dyno rollers and pop the colortune in. Chokes are certainly off when I give it gas to get the thing to start. Gonna go and put the 20's back in. Thanks Les.
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Old 10-23-2012, 09:22 AM   #111
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Quick point of reference.
Bing mixture screws govern fuel. Mikuni mixture screw govern air, on the VM series anyway.
The easy way to distinguish is by where the screw is located. If the screw is between the intake valve and the slide, like on the Bings, it's a fuel screw.
If it's between the airbox and the slide, it's an airscrew.
Also, airscrew normal range should be between 1 1/4 to 1 3/4 turns from seated.
2 1/2 is too far out and indicates too rich of a pilot jet.
I started with a 17.5 and it was way too lean and worked my way up to a 25, recently trying a 30, which might be just a tad rich. Airscrew is set at 1 2/3 of a turn out.
BTW, float level makes a big difference. Make sure the float tang is parallel to the float bowl gasket surface.
If the engine wants to stall on hard decell around town your float level is too high and is sloshing fuel though the pilot jet into the thottle bore.

Kai Ju screwed with this post 10-23-2012 at 11:15 AM
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Old 10-23-2012, 10:11 AM   #112
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Originally Posted by hardwaregrrl View Post
No....too scared to do that.....might try to at least put it on the dyno rollers and pop the colortune in. Chokes are certainly off when I give it gas to get the thing to start. Gonna go and put the 20's back in. Thanks Les.
I think you misunderstood me on the chokes.

I don't know how the Choles work on your particular carbs, but I am saying make sure(confirm) they are OFF. There could be mis adjusted cables, chokes sticking etc. How you would check this is determined by how your carbs chokes work. The lever could be off but the chokes be on, or partially on. They could be chokes or enrichment circuits, that's 2 totally different ways to enrichen. My Mikunis have enrichment circuits, not chokes or strangler valves.

I was wondering about thehow you did the colortune because if you are not checking with the engine loaded, I'm not sure how useful the information is. That's why I originally mentioned that to me, a Colortune is only(may be) useful for checking idle conditions.
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Old 10-23-2012, 02:50 PM   #113
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Quote:
Originally Posted by Kai Ju View Post
Quick point of reference.
Bing mixture screws govern fuel. Mikuni mixture screw govern air, on the VM series anyway.
The easy way to distinguish is by where the screw is located. If the screw is between the intake valve and the slide, like on the Bings, it's a fuel screw.
If it's between the airbox and the slide, it's an airscrew.
Also, airscrew normal range should be between 1 1/4 to 1 3/4 turns from seated.
2 1/2 is too far out and indicates too rich of a pilot jet.
I started with a 17.5 and it was way too lean and worked my way up to a 25, recently trying a 30, which might be just a tad rich. Airscrew is set at 1 2/3 of a turn out.
BTW, float level makes a big difference. Make sure the float tang is parallel to the float bowl gasket surface.
If the engine wants to stall on hard decell around town your float level is too high and is sloshing fuel though the pilot jet into the thottle bore.
Checked floats, and tang is parallel with carb body (upside down), when I got the carbs they were adjusted 2.5 turns out, thought that was crazy?? I'm now on a 20 pilot and 1 3/4 out. Thanks for the info!
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Old 10-23-2012, 03:13 PM   #114
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Originally Posted by Les_Garten View Post
I think you misunderstood me on the chokes.

I don't know how the Choles work on your particular carbs, but I am saying make sure(confirm) they are OFF. There could be mis adjusted cables, chokes sticking etc. How you would check this is determined by how your carbs chokes work. The lever could be off but the chokes be on, or partially on. They could be chokes or enrichment circuits, that's 2 totally different ways to enrichen. My Mikunis have enrichment circuits, not chokes or strangler valves.

I was wondering about thehow you did the colortune because if you are not checking with the engine loaded, I'm not sure how useful the information is. That's why I originally mentioned that to me, a Colortune is only(may be) useful for checking idle conditions.
I have plunger style chokes, when closed it's pretty definitive. I held the carb in my hand and accuated the choke to be sure they closed upon pressing.

Every site I checked on told me NOT to ride with the colortune due to heat blowing out the glass. I just held at certain rpms and watched the color....seemed to behave properly. Went to yellow with abrupt roll on, bunson blue all other times...I have no other method to assist me in syncing the carbs. There is no vacuum port on the TM32's, so I can't use a monometer or a twinmax and me ears aint too good. As far as I can tell, it's a choke....but I'm not sure.
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Old 10-23-2012, 03:42 PM   #115
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Originally Posted by hardwaregrrl View Post
As far as I can tell, it's a choke....but I'm not sure.
I don't think any mikunis have chokes. They all use enrichener circuits I think. When you push down on the lever (or maybe pull up on the black knob in your case) you're opening a valve that allows more fuel in. You're not "choking" off air.
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Old 10-23-2012, 04:28 PM   #116
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+1, it's an enrichener circuit.

Also when checking float level I never turn the carb upside down but set it on the airbox side bellmouth. The tang should fall forward without pushing on the spring that's in the float needle valve.
You'd be surprised at the difference that makes, especially on the carbs with one piece floats that are attached to the float arm.
Mine have the individual floats that 'float' on pins in the float bowl and contact the float arm with pins sticking out the side of the float itself.

I need a Root Beer Float now
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Old 10-23-2012, 04:54 PM   #117
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Originally Posted by Kai Ju View Post
+1, it's an enrichener circuit.

Also when checking float level I never turn the carb upside down but set it on the airbox side bellmouth. The tang should fall forward without pushing on the spring that's in the float needle valve.
You'd be surprised at the difference that makes, especially on the carbs with one piece floats that are attached to the float arm.
Mine have the individual floats that 'float' on pins in the float bowl and contact the float arm with pins sticking out the side of the float itself.

I need a Root Beer Float now
.....gotcha!! I'll check that tomorrow as I'm about to kill the bike. It's driving me batty trying to get it tuned. I put the 20 pilot back in and its running very rough and I'm having a hard time syncing them. I made many mistakes by doing too many things at once....so I'm hands off for now. Other than properly checking the float levels. Thanks guys!!
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Old 10-24-2012, 08:00 AM   #118
Uncle Pollo
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Take it from the top.

Wire check.

Take the ari filter pipes and look and listen for them beimg at the same height and opening and closing at the same time.

Che k for the needles beibg at the same setting
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Old 10-24-2012, 02:19 PM   #119
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Take it from the top.

Wire check.

Take the ari filter pipes and look and listen for them beimg at the same height and opening and closing at the same time.

Che k for the needles beibg at the same setting
Everything is as it was. 165 main/20 pilot 1 3/4 turns out. P2 needle jet, 5fp17 needle in the middle position, 18mm float height. Runs ok, but just isn't very smooth on the low end. Only way to start it is chokes open, and just a little throttle. But the bigger pilot jets exhibit the same behavior on start up but too rich at idle. Bike stumbles on take off with 25 pilot. 17.5, 15? Just seems lean?
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Old 10-24-2012, 06:15 PM   #120
Uncle Pollo
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Originally Posted by hardwaregrrl View Post
Everything is as it was. 165 main/20 pilot 1 3/4 turns out. P2 needle jet, 5fp17 needle in the middle position, 18mm float height. Runs ok, but just isn't very smooth on the low end. Only way to start it is chokes open, and just a little throttle. But the bigger pilot jets exhibit the same behavior on start up but too rich at idle. Bike stumbles on take off with 25 pilot. 17.5, 15? Just seems lean?
Your pilot is smaller than mine and I am at altitude and I start the bike with the enricheners for a few seconds with a little throttle. Satisfied.

Is that the correct needle for your carbs? 5 series.

My VM32 calls for 6 series.
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