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Discussion Starter #1
Hi to all,
New member in trouble.
My V-Star had run about 200 miles only. When pull the clutch to disengage gears (for example to reduce gears) the engine over spin without throttling action. Only stop when I engage a gear or neutral. Also notice higher heating than with my previous V-Star 2008. I did not performed yet the first maintenance post sale.
Can someone help?
Thanks to all in advance
Héctor
 

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does the engine rpm drop after a few seconds or is it always idling fast?

can you look under the tank and see if the throttle is hanging? there are two cables, one pulls it open, the other pulls it shut. Sometime one cable breaks and it gets sloppy, or the freeplay is adjusted too tight and it hangs up, or someone put taller handlbars on the bike and stretched the cables too tight.

High RPM is often caused by a vacuum leak, soneone tried to disable the AIS and missed plugging a hose, or the small caps on the tube just under the carbs where you connect a vacuum gauge are cracked or missing.

The general issue for buying a used bike is how long did it sit with gas in the tank, and no one riding it? If you look in the tank and it looks like anything but clear gas I would drain it, fill it with fresh gas, and some Seafoam. If it looks like coffee in there then dont run it again till you get fresh gas.
 

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Discussion Starter #3
Clutch issues V-Star 650 custom

Hi KCW and all,
First thanks very much for your prompt answer.
I checked as recommended in your msg and nothing look wrong under the tank. Sorry I took couple of days in answering. I was out of town with no WiFi.
But in checking what you suggest I found out that the oil is overfilled in the carter. It doesn’t seem much but I wander if oil overfilling could be the cause of my throttling issues when the engine warm up.
The engine rpm goes high only after few miles running and only drops when it goes to a gear or neutral.
In the sake of clarity, I did not bought a second hand motorcycle. It was brand new from the dealer. It just took an overseas shipment and a couple of years I could not ride. I warmed it up often and winterised it when appropriate. If oil overfilled could be the cause it is nobody fault but mine. I hope you can confirm my hunch.
I will proceed anyway to take the excess oil out. Probably need to clean the air filter.
Please confirm. I will highly appreciate any tip you could give me.
Thanks again.
Hector
 

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if its overfilled by a fraction of a quart I dont think that would make the engine idle fast

If you sit on the bike a hold the front brake with your right hand, and reach down with a small mirror, you can see the oil level in the window. Leaning the bike a bit to the right will make it drop, to the left will push it over the top of the window.

Normally when I fill my VS650 with 3 quarts of oil, after riding a few miles to fill the new oil filter, the oil looks a bit high in the window, maybe a 1/8 inch above the top mark when the bike is full. Leaning the bike just 10 degrees to the right brings it down in the middle, so I know I did not put an extra quart in by mistake. Ive never had any idle issues with the 650 in the last 35,000 miles I put on the odo.

If the bike is a quart over the crank shaft will be spinning hard into the oil surface, and stirring it up into a froth. That could end up blowing out the crankcase breather tube on the top of the rear cylinder head, and into the air intake box on top of the carb.

I guess having some oil injected into the air intake could act like additional fuel and make the bike idle faster, or if its blowing back into the air filter and restricting it, that would be like riding with the choke on.

So... that's something to look at: pull the air filter out and if its not white like paper then replace it. Dont bother trying to rinse it off with a solvent or blow it off with compressed air.

If the bike is a quart over filled you could do the messy partial drain with the drain plug, or get something like a turkey baster and a short tube and see if you can suck it from the oil fill cap opening.

Usually if a bike has sat for a while and then does not run right its because of 10% ethanol fuel breaking down. Even if you use a stabilizer, there is a time limit beyond which it will still go bad.

Simply because the bike sat for a year or more, If you are still using the old gas, drain it all out and add a carb cleaner like SeaFoam when you fill it with fresh gas.

If you already burned off most of the old gas I would still go get a carb cleaner and run that thru for at least a couple tanks of new gas, and see if it resolves the problem. I know it seems like its too simple of a fix, but a good carb cleaner and following the directions on the bottle (do not pour the whole bottle in one tank of gas) has fixed many bikes on this forum over the years.

Its only about $8, and it really does work.
 

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since you did not mention it in your post, a vacuum leak is a common cause of fast idle: Check the caps over the vacuum gauge attachment tubes (just under carbs on left side.

take a propane torch and turn the gas on, but do not light the flame - with the bike idling point the propane flow around the base of the carbs, and the boots, and any vacuum lines (AIS hoses) going to the engine. If the bike idles faster when you point the propane at one area, there is vacuum leak in that area.

Even with a new bike you can have a missing cap, or a loose boot connection causing a vacuum leak.
 

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Hi Hector!
Welcome from East Tennessee. You’re getting great answers from our helpful members. Be sure to post in the Vstar section with any additional questions, you’ll get more exposure. Ride safely and keep us updated.


Sent from my iPhone using Tapatalk
 

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