Dangerous on Center Stand

paikkylee · Post by **paikkylee** » Tue May 03, 2011 1:37 pm

So, after several upgrades and tuning, I'm getting down to some "details". I've noticed that my buddy when idling and put up on the center stand will rev like crazy.

I've narrowed it down to something pulling on the throttle cable, but it doesn't seem to make sense that it would happen only when going on the center stand.

Could I fix it with a longer throttle cable, or is there an adjustment somewhere I'm unaware of?

PeteH · Post by **PeteH** » Tue May 03, 2011 1:51 pm

Just to see if it's actually a center stand issue vs. just having the rear wheel off the ground - when it's up on the center stand, does the rear wheel spin? Does the idle drop back down if you put weight on the seat and put the rear wheel back on the ground (stopping its spin)?

If so, can you just dial down the idle speed at the normal connection point for the cable?

Post by **ericalm** » Tue May 03, 2011 2:05 pm

The actual RPMs are higher on the center stand?

Does this also happen when the scooter's warmed up or just when you first start it?

Could just be the idle. Could be the auto choke.

paikkylee · Post by **paikkylee** » Tue May 03, 2011 3:30 pm

It doesn't always do it, but when it does, the RPMs do drop after putting the brake on and completely go back to normal if I drop it down again (kinda dicey when it's revving at full go).

Eric - it'll do it after a long ride and I've got manual choke now vs. auto choke, so that's not it. I noticed that the mechanic that installed the cylinder kit and the new carb had hacksawed the top off the stock carb, so I didn't know if the cable had been shortened as well, causing it to pull when I put it up on the centerstand (how's that for a run on sentence?)

PeteH wrote:Just to see if it's actually a center stand issue vs. just having the rear wheel off the ground - when it's up on the center stand, does the rear wheel spin? Does the idle drop back down if you put weight on the seat and put the rear wheel back on the ground (stopping its spin)?

If so, can you just dial down the idle speed at the normal connection point for the cable?

Post by **ericalm** » Tue May 03, 2011 5:01 pm

paikkylee wrote:It doesn't always do it, but when it does, the RPMs do drop after putting the brake on and completely go back to normal if I drop it down again (kinda dicey when it's revving at full go).

Eric - it'll do it after a long ride and I've got manual choke now vs. auto choke, so that's not it. I noticed that the mechanic that installed the cylinder kit and the new carb had hacksawed the top off the stock carb, so I didn't know if the cable had been shortened as well, causing it to pull when I put it up on the centerstand (how's that for a run on sentence?)

Manual choke? Hacked carb? What have you done to this poor scooter?

Skootz Kabootz · Post by **Skootz Kabootz** » Tue May 03, 2011 6:13 pm

Just cause it needs to be said, it's never a good idea to leave your scooter running while on the centerstand unless you are on it too.

That said, it sounds like auto choke to me.

paikkylee · Post by **paikkylee** » Tue May 03, 2011 6:37 pm

Simply trusted the wrong mechanic. I think the lesson I've learned finally is that no one cares about my scooter more than I do and that my paranoia makes up for my my total lack of experience.

Think about it. If you're a good "motorcycle mechanic" why are you working on scooters?

ericalm wrote:Manual choke? Hacked carb? What have you done to this poor scooter?

1 Malossi 70cc kit destroyed, 2 malossi pistons, 1 dry seizure later I finally decided to take things pretty much exclusively in my own hands. Slow learner. I'm pretty sure I could have done at least as well without 25 years as a "motorcycle mechanic".

charlie55 · Post by **charlie55** » Tue May 03, 2011 6:59 pm

For testing purposes, how about just loosening the cable adjuster on the carb to the point where it got a ton of slack in it (or just disconnecting the cable at the carb altogether)? The repeat the center stand test.

paikkylee · Post by **paikkylee** » Tue May 03, 2011 7:59 pm

Good idea. I'll give it a shot.

Thanks for the input.

charlie55 wrote:For testing purposes, how about just loosening the cable adjuster on the carb to the point where it got a ton of slack in it (or just disconnecting the cable at the carb altogether)? The repeat the center stand test.

jmkjr72 · Post by **jmkjr72** » Wed May 04, 2011 2:14 am

yeah it proably is something with the cable with the 26mm carb
if you have the oem carb still
this is what i would do
pull the new carb (leave the fuel lines and cable hooked up)
then put on the oem carb and take note of how the cable goes into the carb
my bet is the aftermarket carb is a bit taller and when its on the center stand the rear can droop out and pull a little bit on the cable every now and then
once you see how the oe carb sits again see if you can adjust the tube that comes out of the new carb so it matches the location of the oe carb

or look around and see if you can pull some slack on the cable some where to give you some more slack

paikkylee · Post by **paikkylee** » Wed May 04, 2011 2:23 pm

jmkjr72 wrote:yeah it proably is something with the cable with the 26mm carb
if you have the oem carb still
this is what i would do
pull the new carb (leave the fuel lines and cable hooked up)
then put on the oem carb and take note of how the cable goes into the carb
my bet is the aftermarket carb is a bit taller and when its on the center stand the rear can droop out and pull a little bit on the cable every now and then
once you see how the oe carb sits again see if you can adjust the tube that comes out of the new carb so it matches the location of the oe carb

or look around and see if you can pull some slack on the cable some where to give you some more slack

Aha! It never occurred to me why putting it up on the center stand would cause this, but if it does make it droop slightly, it all makes sense. The problem does go away if I yank a little more slack into the cable, but the fix is only temporary. It comes back eventually. I guess I can just do that before I start it up to warm it up. It feels a little ghetto though.

jmkjr72 · Post by **jmkjr72** » Wed May 04, 2011 11:56 pm

pull your panels and reroute your cable and then zip tie it good and tight so it cant move when you reroute it

toycoma98 · Post by **toycoma98** » Thu May 05, 2011 3:26 am

I just removed my center stand completely. It's so much of a hassle putting up in the center stand. I use a low profile jack when i work on it now that its gone.

babblefish · Post by **babblefish** » Thu May 05, 2011 5:58 am

toycoma98 wrote:I just removed my center stand completely. It's so much of a hassle putting up in the center stand. I use a low profile jack when i work on it now that its gone.

That seems a bit dangerous to me because when my engine is cold, the choke causes the idle to be high enough to engage the clutch. I can just picture my Blur pulling itself off the side stand and into oblivion.

toycoma98 · Post by **toycoma98** » Thu May 05, 2011 10:00 am

babblefish wrote:
toycoma98 wrote:I just removed my center stand completely. It's so much of a hassle putting up in the center stand. I use a low profile jack when i work on it now that its gone.
That seems a bit dangerous to me because when my engine is cold, the choke causes the idle to be high enough to engage the clutch. I can just picture my Blur pulling itself off the side stand and into oblivion.

You're right, i'm in a nice 85 degree weather all year. Thanks for clearing that up for me.