2008 Road Star Running Rough

[RickC]

I have had my 2008 R* for 8 months now. It took me a while to get used to all the noises lol. Just to give a little background on what I have done with the bike before I describe the problem. Bike had 12k miles when I got it, and has 16k now. I put in all new plugs and had the valves/rockers checked 8 months ago. Stock exhaust with holes drilled(stage 2 mod basically). Added extra holes to the airbox and put in a K&N filter. Been running 20w50 Mobil 1 since I got it. No aftermarket fuel manager.

Now, on to the problem. Up till this last week, the bike ran great, and smooth. I could hold the throttle at any level and it was smooth with no misses. I could get it up to 100mph+ and it was pretty smooth(normally only run 80). I don't do burnouts. I'm not super aggressive or anything either. Anyway, this last weekend I went to ride the bike and I noticed there seems to be a bit of stutter/ a miss now when I hold the throttle, and anything above 80 I get a decent amount of vibration. Definitely no loss of power that I can tell though. If there is, it's so small it's unnoticeable. Tried Seafoam in a tank. Ran 2 tanks of gas through it. Probably going to check the plugs this week. Looking for suggestions. Thanks!

Rick
Garland, TX

[Shores]

Run 87 fuel only. Disconnect the battery for a few minutes and then reinstall it to see if things get reset. Loosen the exhaust bolts slightly from front to rear and then tighten them back down. Sometimes this relieves some of the tension in the exhaust which could give you more vibration. How many miles on the plugs? Is the air filter clean?

[davej]

are you sure it is an engine vibration and not something with a tire. Maybe lost a wheel weight? If Metzler tires you may have a belt shift?

[Shores]

are you sure it is an engine vibration and not something with a tire. Maybe lost a wheel weight? If Metzler tires you may have a belt shift?

Yes, and get rid of the lead weights and use either Ride On liquid or DynaBeads per instructions.

[RickC]

Run 87 fuel only. Disconnect the battery for a few minutes and then reinstall it to see if things get reset. Loosen the exhaust bolts slightly from front to rear and then tighten them back down. Sometimes this relieves some of the tension in the exhaust which could give you more vibration. How many miles on the plugs? Is the air filter clean?

I always run 87. I could try the battery disconnect. I did that after I drilled the exhaust and airbox a month or so ago also. Air filter is K&N and barely has 500 miles on it with no rain riding yet. I'll check it though.

[RickC]

Yes, and get rid of the lead weights and use either Ride On liquid or DynaBeads per instructions.

I'm pretty sure it's an engine vibration, but it's hard to be sure. Holding a high idle didnt have a miss before like it does now. Tires did cross my mind early on as I do need to get a new front soon.

[RickC]

So I got new plugs, unhooked the battery for a day to reset computer(I know it only needs like 10 mins), and got a new front tire and had the rear one rebalanced. Definitely still a noticeable engine vibration that wasn't there before. Will probably try doing a throttle body sync this week and see what that does.

[Shores]

So I got new plugs, unhooked the battery for a day to reset computer(I know it only needs like 10 mins), and got a new front tire and had the rear one rebalanced. Definitely still a noticeable engine vibration that wasn't there before. Will probably try doing a throttle body sync this week and see what that does.

I wouldn't mess with the throttle body. There's a slim chance that it got out of adjustment since it ran good last time. I would loosen the exhaust system and retighten it, working your way back and forth from front to rear. Are all four plugs burning about the same color?

[Herrindude]

Any chance the front pulley nut got loose?

[RickC]

I wouldn't mess with the throttle body. There's a slim chance that it got out of adjustment since it ran good last time. I would loosen the exhaust system and retighten it, working your way back and forth from front to rear. Are all four plugs burning about the same color?

All 4 plugs looked almost identical. Normal coloring. I'll check the exhaust, but I haven't heard any leaks. One thing I did notice was a lot of vibration in the handle bars. If I give them a good firm grip, I can make some of the vibration go away. I did change out the risers a while back, so I'm going to take that loose and check it. I wouldn't think it would need the neck nut adjusted yet though. Bike only has 15k miles on it.

[RickC]

Any chance the front pulley nut got loose?

I don't think so, as I have checked it twice in the 6 months I have had it, but I will check it again.

[Shores]

All 4 plugs looked almost identical. Normal coloring. I'll check the exhaust, but I haven't heard any leaks. One thing I did notice was a lot of vibration in the handle bars. If I give them a good firm grip, I can make some of the vibration go away. I did change out the risers a while back, so I'm going to take that loose and check it. I wouldn't think it would need the neck nut adjusted yet though. Bike only has 15k miles on it.

The neck bearings are notoriously dry and loose from the factory so I wouldn't hesitate repacking them and adjusting them. Some vibrations can be caused just from over tightening exhaust, handlebars, etc in a cockeyed position.

[Lug Nut]

What plugs did you use?

[Shores]

Did it run smoother before you had the valves adjusted?

[Lug Nut]

Did it run smoother before you had the valves adjusted?

All the posts inhave read and yamahas inhave owned......I don't think I ever heard a Roadstar running better/"needing" a valve adjustment...but LOTS of people encountering problems after adjusting valves themselves or having them adjusted.

[RickC]

So I finally found what caused a decent amount of the vibration. There were no spacers at either end of the long rod that holds the gas tank on. Not sure how I never noticed that before. I have had the tank off 3 times and never noticed any spacers. Wondering if they fell off with the previous owner. I ordered the correct part online, but for now I stacked some washers in there, and when I took it for a test ride there was a noticeable improvement. Still requires further testing which I will do this weekend with a long ride, but I was pretty happy with the improvement. Thinking back now, It did seem to be more exaggerated of a vibration right after I filled up and the tank was full and heavy. Also found some corrosion between the battery tender connector and the negative terminal. To be continued...

[RickC]

Did it run smoother before you had the valves adjusted?

Didn't notice a change at all when I did the rocker adjustments tbh. That was back in March also. These are newer vibrations. Some of the vibration is gone after fixing the tank, but I still have a some floorboard vibrations I didn't have before. Going to experiment with taking the engine guard off tonight probably and see what that does.

[RickC]

A little less vibration without the engine guard. Did notice whoever put them on used the wrong length bolts also and I could barely spin the washer with the bolt tight. Funny enough, that took away a little knock/tick noise. Probably because under heavy engine vibration the guard was moving a little.