Breathing noise with Mikuni upgrade

Minimichael

Minimichael

Well-Known Member
#3
#3
Shutting off? How so? Not sure it should run at all if your Cam is off by a dot. The breathey noise might just be a characteristic of the carb, too. What size and type mikuni?
 
Olderasteroid137

Olderasteroid137

Member
#4
#4
I realigned cam with dots so thats good. Its vm22 26mm. I didn’t relash valves at all; I need to purchase a feeler gauge. I think there might be an issue with flywheel. It is much harder to pull pullstart.
 
Minimichael

Minimichael

Well-Known Member
#6
#6
What jets are you using? I notice Go Power Sport sells a vm22 with 100 main and 30 pilot ...but then recommends 140 and 17.5!

I've noticed slide carbs can hiss a lot when starting, depending on where the idle is set at. And setting it based on a 30 pilot might be making it even more slurpy-sounding.
 
Olderasteroid137

Olderasteroid137

Member
#7
#7
Minimichael said:
What jets are you using? I notice Go Power Sport sells a vm22 with 100 main and 30 pilot ...but then recommends 140 and 17.5!

I've noticed slide carbs can hiss a lot when starting, depending on where the idle is set at. And setting it based on a 30 pilot might be making it even more slurpy-sounding.
Click to expand...
I’m not sure what jet is installed. This is the carb I have. FVRITO VM22 26mm Carburetor Throttle Assembly Main Jets Kit for Predator 212cc 224cc 196cc Non Hemi Coleman CT200U BT200X Mini Bike KT196 Go Kart 6.5HP GX160 Clone Engine Baja MB200 Performance Parts https://a.co/d/9i5JNpQ
 
Minimichael

Minimichael

Well-Known Member
#8
#8
I watched your video and don't understand why you're concerned about the air noise. Also, how is it shutting off at high speed? You mean high rpms? Sputtering? Lack of fuel? Id make sure you have a bigger main jet in there.
 
ole4

ole4

#9
#9
Olderasteroid137 said:
I realigned cam with dots so thats good. Its vm22 26mm. I didn’t relash valves at all; I need to purchase a feeler gauge. I think there might be an issue with flywheel. It is much harder to pull pullstart.
Click to expand...
if the valves are not adjusted it will be very hard to pull the cord. If you turn off the ignition and it is still hard to pull its not your flywheel, your exhaust lash is off and probably your intake as well. It is not easy to set the lash unless you learn the correct place the engine is in. most times you set it at the wrong cycle or not at TDC.
 
Minimichael

Minimichael

Well-Known Member
#10
#10
Ole4 - Are you saying the lash would be off because of the governor work, or...? I was gonna say decompression trigger?
Olderasteroid - Are you running the stock cam? Also was the Cam gear dot misaligned before? If so, did resetting help the hard-pull problem? Finally, how are you feeding the carb, because I noticed your fuel line looks empty. Shutting off at high speed cud be cuz yer bowl is emptying
 
SAS289

SAS289

Well-Known Member
#11
#11
That's funny. I was just looking at a similar carb kit the other day.

Do the main jets that come with the kit work on the carb you get? In one of the reviews someone said the provided jets will not screw into the carb.

Thinking about getting one. Would like to see how difficult or not they are to set up. I would start with a 115 main on a stock 196 with a header pipe.
 
ole4

ole4

#12
#12
Minimichael said:
Ole4 - Are you saying the lash would be off because of the governor work, or...? I was gonna say decompression trigger?
Olderasteroid - Are you running the stock cam? Also was the Cam gear dot misaligned before? If so, did resetting help the hard-pull problem? Finally, how are you feeding the carb, because I noticed your fuel line looks empty. Shutting off at high speed cud be cuz yer bowl is emptying
Click to expand...
Reading between the lines, he removed the governor and asked about cam timing which means cam came out and lifters probably fell out. Now he puts it back together and 50/50 chance lifters go in the wrong hole. The lifters are the same within +_ a few thou which could affect valve lash. Also push rods probably fell off rockers now 50/50 they are also reversed another couple .0000
 
Minimichael

Minimichael

Well-Known Member
#13
#13
ole4 said:
Reading between the lines, he removed the governor and asked about cam timing which means cam came out and lifters probably fell out. Now he puts it back together and 50/50 chance lifters go in the wrong hole. The lifters are the same within +_ a few thou which could affect valve lash. Also push rods probably fell off rockers now 50/50 they are also reversed another couple .0000
Click to expand...
Them are some excellent deductions, Watson!
 
Olderasteroid137

Olderasteroid137

Member
#14
#14
Got the bike running good. Only downside is that it tops out around 35mph. I probably need to install a bigger jet. Also, the bike only runs when the plunger is up on choke. It idles when the plunger is down, but when I pull the throttle it turns off. If the plunger is up, does that mean the choke is on or off. (I’m pretty clueless about this carb)
 
ole4

ole4

#16
#16
If the brass plunger is up (not the lever) then the enricher is on. If it dies when you turn it's off it's your idle settings. There are 3 parts to getting a good idle setting the pilot jet, the slide height adjustment and fuel mixture screw and they all interact with each other. If you have an air leak it's rews up everything. Your carb does not have a choke
 
SAS289

SAS289

Well-Known Member
#17
#17
Olderasteroid137 said:
Got the bike running good. Only downside is that it tops out around 35mph. I probably need to install a bigger jet. Also, the bike only runs when the plunger is up on choke. It idles when the plunger is down, but when I pull the throttle it turns off. If the plunger is up, does that mean the choke is on or off. (I’m pretty clueless about this carb)
Click to expand...
35 mph but what else has been done to the bike/engine? If everything else is stock that's too much RPM. If you are not going to build the engine for high RPM get a torque converter. It will save the stock 196 from too high an RPM.
 
Olderasteroid137

Olderasteroid137

Member
#18
#18
SAS289 said:
35 mph but what else has been done to the bike/engine? If everything else is stock that's too much RPM. If you are not going to build the engine for high RPM get a torque converter. It will save the stock 196 from too high an RPM.
Click to expand...
Governor is removed. Torque converter installed. I changed to a 120 jet. Just need to find a good fuel mixture screw setting. Still not sure what is best for it. But the bike runs way better now that I put on a bigger jet. Will test top speed tomorrow.
 
Olderasteroid137

Olderasteroid137

Member
#19
#19
when I ride the bike, is plunger supposed to be like this? I can only start and ride the bike when I have it up like this. When I push it down, the bike dies. *also, my spark plug is black. Probably running too lean. I’m having trouble finding a good adjustment for the fuel mixture screw. Can’t get the bike started with what I’m trying.
 

Attachments

Last edited:
Minimichael

Minimichael

Well-Known Member
#20
#20
Can I get a drum roll please? This is a major question and point of confusion circulating on this site. But in my humble opinion, it looks to me like you're running with the enrichokener fully actuated. Choke on.
 
You must log in or register to reply here.
Top