Clutch Engagement at High RPMs

New to the Silver Wing (but not new to scooters) I think I have a problem but before exploring further I’d like to verify that I should be concerned.

I purchased a new 2011 SW, with zero miles, six weeks ago and immediately noticed that when driving off from a stop the clutch didn’t engage until nearly 2,500 RPMs. And when stopping, the clutch would disengage at about the same RPMs (around eight MPH give or take). Since this my first SW I supposed this was normal for the SW and, although it felt strange to me, I would get used to it. (I will add that driving off at 2,500 RPMs did feel unsafe.) This clutch activity was different from my previous scooter, a Piaggio MP3 500, where the clutch would engage/disengage at a few RPMs above idle.

My concern about the clutch heightened yesterday when I tried to drive off from a gravel parking lot. The rear wheel tended to spin up gravel when the clutch finally engaged. I couldn’t drive off slowly without spinning the rear wheel.

Is this normal clutch operation or do I have a problem that should be corrected? Any guidance or related information would be appreciated.

I don't remember exactly where the clutch begins to engage, but I believe it's less than 2,000 RPM. It might not fully engage until higher.

Disengaging at around 8MPH doesn't sound unusual.

Mine engages about 2300-2500 rpm. It can be changed by changing springs in the clutch. I used an aftermarket clutch for a while that allowed a higher rpm before engaging, allowing the engine to get closer to its power band before engaging. It helps to reduce the rumble from the dash on take-off.

Yours sounds normal; don't worry about it.

jmaslak wrote:

I don't remember exactly where the clutch begins to engage, but I believe it's less than 2,000 RPM.  It might not fully engage until higher.

Disengaging at around 8MPH doesn't sound unusual.

Thanks jmaslak for your reply. I'm thinking my clutch operation is normal.

buddy19520 wrote:

Mine engages about 2300-2500 rpm.  It can be changed by changing springs in the clutch.  I used an aftermarket clutch for a while that allowed a higher rpm before engaging, allowing the engine to get closer to its power band before engaging.  It helps to reduce the rumble from the dash on take-off.

Yours sounds normal; don't worry about it.

buddy 19520,

I appreciate your "don't worry about it" advice. And I won't. I feel confident now that my SW is normal.

Come to think of it, my Piaggio MP3's dash would rumble on take-off, probably because the low RPM engagement.

Three things I'd suggest, particularly seeing you might also be at a bit of alititude:

1) My bike came with an idle speed that was too low. You might make sure it's idling at the right point. Note that there are *3* screws you can easily reach through the adjustment hole - you want the one that is straight down, not one off to either side (or you'll be buying two vacuum gauges to fix it!). I suspect altitude was the culprit here. Raising the idle speed helped reduce the amount of throttle needed to get it to move.

2) My bike also had a bit loose throttle when new. I took the slack out using the adjuster at the grip, and that helped (note you need a small amount of slack for the return to work right).

3) If you are trying to do things like parking lot turns and such, a tiny bit of rear brake will let you increase RPMs for a given speed by essentially slipping the clutch. It's not something I'd do a lot of (it's not a motorcycle-type wet clutch), but used when needed it can work fine. Remember that these bikes have combined braking, so light pressure is what you want on the brake handle - too much and you'll also apply front brake, which is a good way to go down in a parking lot!

After doing #1 and #2, I liked the handling at take-off and slow speed much better - it was much easier to control.

jmaslak wrote:

Three things I'd suggest, particularly seeing you might also be at a bit of alititude:

1) My bike came with an idle speed that was too low.  You might make sure it's idling at the right point.  Note that there are *3* screws you can easily reach through the adjustment hole - you want the one that is straight down, not one off to either side (or you'll be buying two vacuum gauges to fix it!).  I suspect altitude was the culprit here.  Raising the idle speed helped reduce the amount of throttle needed to get it to move.

2) My bike also had a bit loose throttle when new.  I took the slack out using the adjuster at the grip, and that helped (note you need a small amount of slack for the return to work right).

3) If you are trying to do things like parking lot turns and such, a tiny bit of rear brake will let you increase RPMs for a given speed by essentially slipping the clutch.  It's not something I'd do a lot of (it's not a motorcycle-type wet clutch), but used when needed it can work fine.  Remember that these bikes have combined braking, so light pressure is what you want on the brake handle - too much and you'll also apply front brake, which is a good way to go down in a parking lot!

After doing #1 and #2, I liked the handling at take-off and slow speed much better - it was much easier to control.

jmaslak,

Thanks for the tips. The altitude of Las Cruces is around 4,300 so I think I will raise my idle RPM from 1,100 to 1,300 to see if that helps.

My throttle slack is right on so I'm not going to fuss with that.

I can see how light rear braking will help so I'll try your technique the next time I park in the gravel parking lot.

Based upon what you've told me, I think my concern simply boils down to getting used to the SW's clutch engagement at higher RPM than what I am used to. My Piaggio MP3 500 idled at 1,500 RPM and the clutch engaged around 2,000 RPM. Compare that to the SW idle at 1,100 and clutch engagement around 2,400.

Thanks again, jmaslak.

jasunday (Jim)

FYI, the 2011s use fuel injectors, not carburetors. Not sure there are adjustments you could make to raise the RPM from there.

DarthJ wrote:

FYI, the 2011s use fuel injectors, not carburetors.  Not sure there are adjustments you could make to raise the RPM from there.  

DarthJ,

I checked the Owner Manual for the idle adjustment screw and found it located under the seat. It adjusted without a problem.

jasunday (Jim)