Off idle throttle response on/off

[caseyjones955]

I have searched a bit and found nothing on this. I noticed the throttle difficult to modulate just off idle, leaving an intersection while turning was a very delicate balance of the clutch and throttle. On my driveway (3 miles of washed out dirt) every little bump caused little throttle blip. It does not feel out of synch or anything, the shop just jetted and synced everything up before my purchase of it and it feels great. Off idle it is very much an on/off switch. Newly purchased, yesterday was my first ride on it to get it home.

Is that just the way it is? I can get used to it no problem but if this indicates maladjustment or some other issue I would like to address it. All other riding dynamics feel pretty decent, I havnt given it to much hell yet though as I'm a little rusty. Any links or suggestions welcome.

Thanks much.

 

[blaxmax]

How do the plugs look?
Maybe a/f mixture screws need adjusting or change plug gap.

 

[davesax36]

Mine is like that. It seems really snatchy, especially in 1st gear.

 

[great white]

I don't think it's limited to the vmax. My 1200 venture is the same. Very difficult to be smooth off idle....

 

[caseyjones955]

Snatchy and lashy are the best ways to describe her behavior. I'll have a look at the plugs, the carbs were just jetted and gone over but I know that doesn't mean they are right although it was done at a reputable power sports shop.

My last big bike was a 2000 Sprint ST with perfect EFI mapping and excellent everything. I can tell the Max is a completely different creature with a very different attitude, if this is part of her charm I'm good with that. I can see how an inexperienced rider could get into a lot of trouble with one of these! I'll check plugs, give her an Italian tune-up and see where we're at.

Thanks for the quick guidance.

 

[great white]

One thing that helped me a fair bit was taking most of the freeplay out of the throttle cables.

I left just enough that it's not affecting the idle, but it's tight enough that the carbs respond as soon as I rotate.

That took out a little uncertainty as to when the power was going to hit.

 

[liptoss]

Sounds like you have a Stage 7 jet kit in it.

 

[dannymax]

+1 I'd play around with the cable adjustment a little....think too much or too little free play can cause this to happen.

 

[blaxmax]

With a push pull you should be able to find the right spot (tension wise) but out of all the bikes i've ever owned the position of the vmax's carbs being cv's and angled like downdrafts require constant attention. Letting them sit for a small period of time will cause passages to gum up. Uneven float bowls will cause them to act up.
I have found it easiest to start it up at least every other day and let the gas that has been sitting clear out and before walking away running the fuel pump until all the carbs are full of gas.
You can't go wrong by reading the plugs.

 

[blaxmax]

Snatchy and lashy are the best ways to describe her behavior. I'll have a look at the plugs, the carbs were just jetted and gone over but I know that doesn't mean they are right although it was done at a reputable power sports shop.

My last big bike was a 2000 Sprint ST with perfect EFI mapping and excellent everything. I can tell the Max is a completely different creature with a very different attitude, if this is part of her charm I'm good with that. I can see how an inexperienced rider could get into a lot of trouble with one of these! I'll check plugs, give her an Italian tune-up and see where we're at.

Thanks for the quick guidance.

Efi is going to act different than constant velocity because of the cdi control is heat sensitive and compensates for it.

 

[DMAN999]

My throttle play is set properly according to the manual but it's still got monster torque in 1st gear and is very touchy.
Vmax Mike and I did 1st gear mini wheelies all through Johnstown during the Thunder Parade a few years ago.
Whack the throttle and the front jumps up two feet or so.
Mine is stock and his had a Stage 7 kit with UFO pipes.

That's just the way it is and something you need to learn to compensate for.

 

[caseyjones955]

Thanks, I was thinking the throttle barrel was a little loose, it's within spec but I did consider snugging it up a touch. I will do my best to avoid fuel tainted by ethanol as I do on all my vehicles. I know this shop just did the carbs and when I went to look at the bike it would not take throttle at all so the jets were clogged just from sitting a short time.

I'll add throttle barrel adjustment to the short list of to do items before I go head into the hills for an afternoon.

 

[Traumahawk]

Dmann is right....its very touchy.....and if everything is running right, thats how it is. If its NOT TOUCHY.....then you have to start looking for a reason why.

Your used to bikes with EFI....being very smooth...etc. Your now riding on a bike that is the equivalent of a '70 Hemi Cuda.

Brutal is just a good way to describe it.

 

[thor_eyerdhal]

A good Sync of carbs and it will be smoother (even with S7)

 

[caseyjones955]

The 955 was my first EFI bike. No doubt I loved it. I choose it over the VFR and several others just because it was astonishingly well sorted and mapped. I was looking at Tbirds and Rocket IIIs before I stumbled onto the Vmax. I even checked out a VTX1800 but it bears a strong resemblance to a UAM. Something about the Max pulled me right in, all the nostalgia and recollections of my ride on one way back when. I completely overlooked the carb thing to finally be a Max owner. The idiosyncrasies of carbs are well worth the price of admission.

I am happy to know that this is regarded as somewhat normal behavior. Just from the ride home I know that it will be a comfortable, capable and fun bike.

I saw the blower kits with the Holley 4bbl, has anyone tried this setup with something like a single plane NA manifold?

 

[caseyjones955]

I had it out today with ethanol free fuel and a few capfulls of Sea Foam, did the Italian tune-up and was able to get used to the throttle characteristics in no time. High gear throttle roll-ons will cause a real misfire starting at 4000rmp and will clear up by 5500. Feels like fuel starvation. its fine if I accelerate gradually and its strong down low and up high.

I love this bike already, this V4 is magical haha.