Problem with throttle operation

I have a question about the operation of the throttle on my bike. But first let me describe the problem or issue I have before I ask the question.

I have a 2009 SilverWing that I bought at the end of 2010. It had not sold for some reason. Although the 2010 bikes were in the showroom this 2009 was left over. I got a great deal on it and rode it for a short time last fall. It is in storage now. Last fall, I immediately noticed what may be a problem with the throttle.

I used to have a Honda Helix, 250cc. When I rode that bike at say 30 or 40 miles and hour and then closed the throttle quickly and completely it would coast at high speed at first and then gradually slow down. It was very similar to what happens in a car when you take your foot off the gas peddle. It continues to coast and gradually slows down.

On my 2009 SilverWing I was surprised to find when I closed the throttle quickly and completely the engine RPMs drppped quickly and the bike slowed down quickly. It did not coast and gradually slow down. I found if I wanted to slow down gradually I had to slowly and steadily close the throttle instead of closing it completely and all at once.

Is this type of throttle operation normal? Is my throttle operating properly? Do you find that when you close the throttle completely at high speeds (20, 30, 40 MPH etc.) the bike slows down quickly and does not coast at higher speeds and then gradually slow down? I am wondering if I need to have a Honda service person check out the throttle operation this spring. The bike is still under warranty so it should not cost me anything.

I welcome your comments.

There is always a possibility that the engine breaking is excessive on your bike. However...
Engine breaking is a normal safety feature on the Silverwing.

There is no reason you can't have a Honda professional look at it under warranty, since as you noted, it should cost you nothing.

Dan

First check idle speed---I think shop manual says around 1400rpm. Too low can be sudden drop off of engine speed. Nothing wrong with engine braking. All rubber band drive scooters have drop off of engine connected to rear wheel at somewhere between 5 and 15 mph. Yours different, take to Honda Dealer.

Your bike was not left over because of throttle action......maybe because they cost so much.

SilverWing different than Helix( rode Helix 150,000 miles) some ways better, in other ways not so good---like no built in trunk,or easy to adjust valves.


John Grinsel

Just a couple of things to check or rather think about.

Its a brand new bike, you don't say how many miles its done?..... Everything on it, including the engine is still going to be rather tight! Things take time to bed in and loosen to the correct tolerances. My wifes new car took about 10,000 miles to free up to the point were it was doing the quoted 'average' mileage for use.

How far are you riding to 'test' the coasting??? I notice that in cool conditions my bike seems to do the same thing, initially I thought the parking brake was on (another thing to double check) but came to realise that its the autochoke mechanisum keeping the mixture a little richer for longer. Are you actually getting the machine up to normal operating temp before testing it?? If not then you will probably get this effect.

If you are riding 15-20 miles, the machine reaches normal operating temp and you are still getting this effect then initially I'd monitor it for a while and if it persists then get it back to the shop under warranty.

midlandchip wrote:

On my 2009 SilverWing I was surprised to find when I closed the throttle quickly and completely the engine RPMs drppped quickly and the bike slowed down quickly. It did not coast and gradually slow down. I found if I wanted to slow down gradually I had to slowly and steadily close the throttle instead of closing it completely and all at once.

Sounds like the default SilverWing behavior. A Power Commander can remap the fuel injection, then you can adjust the engine braking.

Is engine breaking normal in a Silverwing? Yes.
Is it noticeable? Very.
What causes it? The direct link between the rear wheel and engine when the clutch is engaged.
What clutch, it's a scooter? Yes, but there is a centrifugal clutch in the final drive. This clutch will disengage once your speed drops to around 10mph.

What you're describing is very normal.

I once rode a friend of mine's 250 racing bike and I was shocked to find no engine braking at all. It was a very odd adjustment because it actually felt like the throttle was stuck open when you let off on the gas. Very disconcerting at first. He told me that's how racing bikes are setup.

Your description of engine braking behavior sounds very normal to me. The Silver Wing will not 'coast' until you get to a fairly low speed (10-20mph) when the centripetal clutch disengages.

No harm in having your shop check it out though, since the bike is still under warranty.

Sounds normal to me too.

Thanks for all the comments. I'm not going to worry about it and I will simply adjust to riding this bike. But the throttle operation is certainly different from what I was used to on my Helix. However, when I take the SilverWing in for its 600 mile checkup this spring I will mention the throttle operation and see what the Honda service tech says. Thanks for your help.

MidlandChip

I moved from a Suzuki Burgman to the 'Wing' and I have to admit to a period of adjustment. The 'Wing' is a different machine but for all the right reasons.

It is a pleasure to ride and the engine braking is a financial saving!! I don't use the brakes a quarter of what I used to, saving wear on pads and discs. All it takes is a wee amount of forward vision and sensible riding. All too many times you see bikes racing up to the rear of traffic then brake sharply looking quite unstable.

Enjoy getting used to the Silver Wing, you will adapt to its ways.

Sounds normal to me.

If you think the Swing has noticeable engine braking, you should try a Burgman 650! The extreme engine braking on the 650 is one of the reasons that I went with the Swing.

Prior to the Silverwing, I had a Chinese 150. When I let off the throttle, it coasted very freely. It took me some time to get used to the Silverwing. You will find it is helpful when riding hilly or curvy roads.

When my Silver Wing was new it would decelerate quickly when I came off the throttle quickly. That abated with some time and braking in ware.