VM26 carb on my Brozz (questions)

Hancadam · 03-20-2019, 08:47 AM

Hi everyone.

I put my vm26 carb on my Brozz to get better tuning ability and because the stock one is very cold natured. But, have ran into an annoying problem.

When letting off the throttle from a higher speed run, it often dies. I moved the needle clip down one, and this helped reduce that from happening to about 50% of what it was doing prior, but I feel like this negatively affected the overall performance. After moving the clip down one notch, it seems to have lost some top end and acceleration, although minor. Which makes me think the jetting is overall to rich possibly. Should I move the clip up instead? Main jet to big?

With the new carb, bike starts and idles perfect with no choke cold. With the old carb, it had to be choked and throttle given, for a minute or so, to keep it running. Once warmed up it performed fine.

Specs on the jetting:
25 on low speed
110 on main
Both jets are genuine minkuni from jets r us.
I also have a 115 for possible exhaust mods later on.

Bike is completely stock otherwise.

Wanted to see what others thought before taking it back down. Hoping someone has ran I to a similar circumstance before. I will run out and check the plug in a hour or so.

Hancadam · 03-20-2019, 10:08 AM

Here is the plug, looks pretty good to me. Bike has 130 miles on it, put the plug in @ 10miles. Of course that's a mix of the two carbs though.

Hancadam · 03-20-2019, 07:06 PM

I think I'm on the right track. Totally forgot about the mixture screw. Bottomed it out, and moved it out to about 1.75 turns. Bike runs better than it ever has, low and top end, but the idle still drops out, sometimes stalling from high speed deceleration. I checked the gas cap just to make sure, no vacuum. I think moving the clip once more may solve it.

tarote9025 · 03-20-2019, 07:21 PM

Im interested in seeing how yours pans out im trying to dial mine in right now i have the little brother so to speak of the brozz the shark and am running the same carb and jets as you i do have the exhaust on mine however. What needle clip position is yours on im 1.5 turns out and middle position on the clip. Idle is perfect with the 25 imo. I was running a 30 pilot 100 main and had the same issue when declerating i think it might be more about the rpms then the carb cause it would only happen sporadically while going from full throttle in 5th to a quick stop at a light.

Hancadam · 03-21-2019, 09:34 AM

My needle clip is one down from the middle. I think I'm going to try one more movement down.

On mine, after a long(ish) higher speed run, it will die, or idle will drop to very low. If I help it recover with just a little throttle, it recovers and stabilizes back to a normal idle. Which all sounds lean to me.

I will keep tinkering and let you know. Other than the above, bike is running great.

Hancadam · 03-22-2019, 07:17 PM

I figured it out. Needle jet needed to be moved up, to lean it out apparently. When I 1st lowered the clip, it must have seemed better because of the low speed adjustments I made.

All is well now.

03-20-2019, 08:47 AM	#1
Hancadam Join Date: Nov 2007 Location: Tennessee Posts: 201	VM26 carb on my Brozz (questions) Hi everyone. I put my vm26 carb on my Brozz to get better tuning ability and because the stock one is very cold natured. But, have ran into an annoying problem. When letting off the throttle from a higher speed run, it often dies. I moved the needle clip down one, and this helped reduce that from happening to about 50% of what it was doing prior, but I feel like this negatively affected the overall performance. After moving the clip down one notch, it seems to have lost some top end and acceleration, although minor. Which makes me think the jetting is overall to rich possibly. Should I move the clip up instead? Main jet to big? With the new carb, bike starts and idles perfect with no choke cold. With the old carb, it had to be choked and throttle given, for a minute or so, to keep it running. Once warmed up it performed fine. Specs on the jetting: 25 on low speed 110 on main Both jets are genuine minkuni from jets r us. I also have a 115 for possible exhaust mods later on. Bike is completely stock otherwise. Wanted to see what others thought before taking it back down. Hoping someone has ran I to a similar circumstance before. I will run out and check the plug in a hour or so. Last edited by Hancadam; 03-20-2019 at 09:18 AM.
	0

03-21-2019, 09:34 AM	#5
Hancadam Join Date: Nov 2007 Location: Tennessee Posts: 201	My needle clip is one down from the middle. I think I'm going to try one more movement down. On mine, after a long(ish) higher speed run, it will die, or idle will drop to very low. If I help it recover with just a little throttle, it recovers and stabilizes back to a normal idle. Which all sounds lean to me. I will keep tinkering and let you know. Other than the above, bike is running great. Last edited by Hancadam; 03-21-2019 at 09:35 AM. Reason: Fat fingers
	0

03-20-2019, 10:08 AM	#2
Hancadam Join Date: Nov 2007 Location: Tennessee Posts: 201	Here is the plug, looks pretty good to me. Bike has 130 miles on it, put the plug in @ 10miles. Of course that's a mix of the two carbs though.
	0

03-20-2019, 07:06 PM	#3
Hancadam Join Date: Nov 2007 Location: Tennessee Posts: 201	I think I'm on the right track. Totally forgot about the mixture screw. Bottomed it out, and moved it out to about 1.75 turns. Bike runs better than it ever has, low and top end, but the idle still drops out, sometimes stalling from high speed deceleration. I checked the gas cap just to make sure, no vacuum. I think moving the clip once more may solve it.
	0

03-20-2019, 07:21 PM	#4
tarote9025 Join Date: Apr 2017 Location: miramar beach fl Posts: 112	Im interested in seeing how yours pans out im trying to dial mine in right now i have the little brother so to speak of the brozz the shark and am running the same carb and jets as you i do have the exhaust on mine however. What needle clip position is yours on im 1.5 turns out and middle position on the clip. Idle is perfect with the 25 imo. I was running a 30 pilot 100 main and had the same issue when declerating i think it might be more about the rpms then the carb cause it would only happen sporadically while going from full throttle in 5th to a quick stop at a light.
	0

03-22-2019, 07:17 PM	#6
Hancadam Join Date: Nov 2007 Location: Tennessee Posts: 201	I figured it out. Needle jet needed to be moved up, to lean it out apparently. When I 1st lowered the clip, it must have seemed better because of the low speed adjustments I made. All is well now.
	2