Highway speed vibration

[Jethroish]

Started to get a vibration today at 60mph. Bike accelerates great and pretty smooth. But got on the throttle heavy at 60 mph in 5th gear and it felt like an off-balance tire or an engine vibration.

I have been thinking that I need to get the carbs synced, so I immediately thought that maybe one cylinder was getting fuel starved at high demand, but it did not do this high rpm in lower gears.

 

Carbs out of sync? Just need a good cleaning?

 

I was at WallyWorld so got a can of SeaFoam and put half of it in with full tank. I'll give that a try first. I also checked to make sure all plug wires were on.

My other thought is, as I have read here before, that getting on the throttle hard in 5th gear at 60mph is just not gonna get it done. No torque.

 

Am I on track or missing something?

 

Bike is 2007 RSV, 12,000 miles, fresh oil change with Mobil 1 MC 10W40, rear end fluid changed at 10,000 miles.

[Jerry W]

My experience is that these engines do better at higher rpm's. Rather than open it up at 60 in 5th gear, you might try downshifting to 4th and then open it up. I am thinking you will get much better results.

[flb_78]

My experience is that these engines do better at higher rpm's. Rather than open it up at 60 in 5th gear, you might try downshifting to 4th and then open it up. I am thinking you will get much better results.

 

yep. hell, at 60, I'd still be in 3rd.

[V7Goose]

Yes, you do need to sync the carbs. They may be OK, but if not, that will absolutely cause the hammering. BUT, as others have said, 60 MPH is on the absolute low end of what you should be at when doing a top-gear roll on! Get those RPM over 3,000 before you do that, and the bike will be much happier.

[Squeeze]

That all said, these lower RpM's and a Lot of Load on the Motor will not do any good on the Crankshaft Bearings. Full Throttle is Ok, when the Revs are beyond 3.5 k. Constantly doing full Throttle Roll On's from 3k are stressing the Bearings a Lot and can cause premature Wear.

[BuddyRich]

Yep, I'm still in 3rd at 60.

[Jethroish]

Just to clarify, my 30 mile ride from home to work is all in a 55mph zone. I normally have the curise set at 60 - 62, in 5th gear for that ride.

This vibration is something that, maybe did not just begin, but such that I really noticed it.

I'll be riding it all weekend and keep tabs on it.

[SaltyDawg]

Like everyone else has said 60 in 5th is low speed for hard throttle twist. If it accelerates fine through the other gears then I wouldn't worry about it just drop to 4th or even 3rd and hit it.

 

It's possible that your plugs need to be changed also.