VM22 boggs with throttle

[SAS289]

In post #8 you said the governor kicks in at 5500 RPM. Once you install a slide carb the governor can no longer function because it is not connected to the throttle on the carb.

In my opinion there are too many variables to consider for an RPM number the stock internals are good to. I would keep it under 5K RPM with short oil change intervals. But that's just me.

 

[sparkwizard]

^^^^^BINGO^^^^^
You still have governor parts spinning around inside your engine. You DO NOT have a functional governor.
Maybe it's just me, but the whole idea of slapping a motorcycle carb on a utility engine to make it go faster makes no sense.
If the owner does not even comprehend how the throttle linkage and governor work YET, how do they make the jump to assuming they are prepared for all of the problems they are causing by their actions? If your reason for installing the motorcycle carburetor was to go faster, by definition, you plan to overrev the engine, which is dangerous. Keep your son off of this one. Don't let Mom ride it, either.

 

[sparkwizard]

Today is Friday. This topic was posted Tuesday. Why can't I get this kind of shipping service from Amazon sellers?
My Spidey senses are tingling here.

 

[TheMattHouston]

^^^^^BINGO^^^^^
You still have governor parts spinning around inside your engine. You DO NOT have a functional governor.
Maybe it's just me, but the whole idea of slapping a motorcycle carb on a utility engine to make it go faster makes no sense.
If the owner does not even comprehend how the throttle linkage and governor work YET, how do they make the jump to assuming they are prepared for all of the problems they are causing by their actions? If your reason for installing the motorcycle carburetor was to go faster, by definition, you plan to overrev the engine, which is dangerous. Keep your son off of this one. Don't let Mom ride it, either.

The reason I got two was to modify with one and keep the other stock while we LEARN about them. I know the flywheel can fragment over 5800 RPMs which I've said it doesn't exceed. So there is no physical danger riding this one and I am the only one that rides the modified one right now. The only other risk is blowing a cheap motor then getting to replace or rebuild it and learn more.

 

[sparkwizard]

What keeps it from exceeding 5800?

 

[Minimichael]

Who are you gonna sue if it fragments below 5800?

 

[TheMattHouston]

What keeps it from exceeding 5800?

Not sure, I put a tachometer on it and drove it and it bounced between 5500-5600. I've read that different motors have different top ends and 5500-6000 is pretty average.

 

[TheMattHouston]

Who are you gonna sue if it fragments below 5800?

No one......

 

[sparkwizard]

I have seen fairly new engines grenade violently with the governor still working. I would never spin a new, untested stock engine over governed speed. We can't stop you, but we have to warn you.

 

[TheMattHouston]

I'm going to put less than 10-15 hours on this motor before I swap the internals in February, none of which will be held at max RPM. These are for riding trails on my ranch, anything over 25mph is uncomfortable. I am only building one out for fun and see if the torque helps with climbing hills.

I have seen fairly new engines grenade violently with the governor still working. I would never spin a new, untested stock engine over governed speed. We can't stop you, but we have to warn you.

I don't plan on it. Thanks for the multiple warnings. That is the reason I installed the tachometer so I can monitor the RPMs.

 

[sparkwizard]

It will be interesting to see which one climbs better, the stock one or the hot rodded one.
My bet would be on the stock one.
Have fun and be safe.

 

[MJL]

Not sure, I put a tachometer on it and drove it and it bounced between 5500-5600. I've read that different motors have different top ends and 5500-6000 is pretty average.

You are likely hitting valve float.