2007 Bandit 1250 ABS: 660 miles ... Vibration

[billincnetraljersey]

I adjusted and lube the chain last night at 630 miles last night.  This morning on my way to work, I noticed a vibration.  First I thought it was the road surface, but it is the bike.  At 6th gear going about 75mph, it is there.  Drop to 5th gear, it is diminished, but still there.

Possible cause:

1/  I'll have to check the tire pressure.  Have been so busy, I have not even check the tire pressure once.  I am so bad.

2/  Is it possibly the loose chain that kept it so smooth up till now?  The chain was really loose, the slack was more than 2 inches!  Now it is within spec, 1.2 inch.  Why would the manual say to check & adjust at 600 miles?  I would think a new chain will stretch a lot and it should be check & adjusted at shorter interval to avoid jerking on a loose chain during throttle on/off.  That jerking probably do more stress to the chain.

3/  The break-in have reach the point where things have loosen up and expect to have more noise & vibration.  Up till now, it feels like an electric motor.

Bill

[ZenMan]

You may have gotten your rear wheel a tad out of alignment when you adjusted the chain. Try checking the increment marks in the swingarm behind the axle slider... it has to be exactly equal on both sides.

Also you may have adjusted it too tight... the 1.5 inches of play should be measured with the bike on the ground, not up on the centerstand.

It's normal for a new chain to stretch a lot in the first 5-600 miles... especially with all the torque this bike has. Mine was about one inch too loose when I adjusted it at 500 miles.

Generally I check and lube my chains every 300 miles.

[pmackie]

Likely still need to "Sync" the throttle plates in those throttle bodies? Ask about it on its mandatory 1st dealer inspection/service.

Most inline fours are going to have a patch of vibration at some point in the rev range. Some notice it more that others.

Let us know how it progresses, because I'm curious. I may have to "update" the little 600 at some point. (Not this year though...I can still keep up with the 1200's based on my recent ride with Red01 and Bobcat).

[CWO4GUNNER]

[billincnetraljersey]

I adjusted the chain while it is up on the center stand.  So, if the wheels are on hte ground, the chain should be tighter, correct?  If that is the case, it probably cause more vibration ... I hope that is the problem because it is an easy solution.

The alignment should be correct.  I counted the exact number of turns on the adjustment screw, referenced to the stock setting.

I doubt it is the throttle body sync.  The previous day going to and from work there were no vibration.  Up until I adjusted the chain, it was running really smooth.  

If it is the throttle body that needs sync, what would happen if I just leave it as is.  Any harm other than more vibration?  For sure, it can't be worst than my previous bikes.  I am running out of time in the prep for my coast to coast round trip.

Manditory first service?  I was just going to change the oil & filter and check all the nuts and bolts, that is all.

[ZenMan]

I adjusted the chain while it is up on the center stand.  So, if the wheels are on hte ground, the chain should be tighter, correct?

Correct. It will tighten when you take it off the centerstand. The adjustment should be done with the bike on the sidestand.

Ideally you should check it with someone near your weight sitting on the bike. It should have about 1" play then.

The alignment should be correct.  I counted the exact number of turns on the adjustment screw, referenced to the stock setting.

That's fine as long as you don't go back in on the turns. When you loosen the adjusters, you have to get the axle to slide forward up against the stops, either by kicking the rear tire from the back or stepping on the chain to pull the axle forward. Using the reference marks is the recommended method.

I doubt it is the throttle body sync.  The previous day going to and from work there were no vibration.  Up until I adjusted the chain, it was running really smooth.

Correct!  

Contrary to un-popular belief, I knew those throttle bodies needed to be synchronized. when the time comes I will have to invest in a another Morgan Carbtune.

CWO, you haven't been paying attention to our discussion about this in another thread... but that's par for the course.    

It's called a Morgan Carbtune for a reason, y'know.  

[CWO4GUNNER]

[Red01]

Using the reference marks is the recommended method.

Only use the reference marks once you've determined by measurement that they are the same on both sides. Those marks are not stamped on with precision!

[rkfire]

Based on the fact it was fine before the chain adjustment, then a new vibration was noticed, I'd agree the chain is either a little tight, or a little cockeyed.

I disagree with using the stamped marks on the swingarm tho. Mine is a full mark off from being correct. It drove me nuts the first chain adjustment, until I actually messured the marks to the swingarm pivot and found they're off by about 1/8 inch. Some use the string method, but after measuring mine, I use (for example) the 4th on one side and the 5th mark on the other side.

On the sidestand is the way to check tension, as mentioned above. One tip though is to tighten the axle nut with the wrench about the 1-2 O'clock position so that the force pushes the wheel forwards, keeping the axle against the stops, rather than pulling the axle loose from the stops.

[ZenMan]

Pay attention. I said "Using the reference marks is the recommended method."

That's what it says in the manual. That makes it the recommended method.

How's that for detail niggling and nit-picking?  

Sheesh.    

If Bill followed the steps I described and found the wheel to be misaligned, then the next step would be to measure the marks to make sure they were true.

I measured mine before I started and they're right on. It's a good idea to make sure.  

[ZenMan]

Another still required practice in spite of FI.

"In spite of?

I swear, CWO... everytime you pretend to know something about fuel injection, it becomes more obvious how much you don't know.    

[txbanditrydr]

You can make a simple block that clamps to the rear sprocket and uses a straight rod that projects forward along the chain - this gives you a much more accurate indication of proper alignment.

Something like this... although my woodshop came in real handy - and a carbon fiber arrow shaft could be substituted for the brass rod.

[billincnetraljersey]

I assume the bike comes from the factory with the rear wheel aligned, regardless of the accuracy of the stamp marks?  Or, does the factory use the stamped alignment marks on the swing arm to do the alignment?

I miss my shaft drive already :)

-bill

[rkfire]

How's that for detail niggling and nit-picking?  

Sheesh.    

:

oh boy,  

[CWO4GUNNER]