My tyres were badly wore down, so I got new tyres fitted today (Bridgestone T30 Evo), but after getting the tyres fitted, I noticed a loud whining noise coming from the front end around 25mph and also a very noticeable vibration through the handlebars and footpegs at around 20mph. I brought the bike back to the tyre fitters where he checked both wheels and even replaced the front tyre just to be on the safe side. He didn't think there was anything wrong with the front wheel; he suspects it's to do with the chain. He checked the wheel alignment with his laser rig etc. and he loosened the chain a bit as he thought it was a little too tight. He mentioned there being a tight spot on the chain.
The problem is that this issue definitely didn't exist before I got the tyres changed today, so I find it hard to believe that it's the chain causing the issue.
The only other point to note is that my previous front tyre was a 120/70 instead of 110/70. Now that I have the correct size on the front, the bike handles much better.
Things I'm planning to do to try to diagnose the issue: Increase the air pressure of each tyre to around 42R 36F, because I asked the fitter what pressures he sets them to and he said 2.5 and 2.3 (or 35 and 33PSI I think). I'm a very big guy and I think the higher pressures will be better for me, though I don't know if low pressures would cause the symptoms I'm experiencing. I'm also going to clean and lube the chain to see if that makes a difference.
Any ideas what this could be?
Thanks in advance.
Check the chain adjustment as per the handbook-its quite a bit with the suspension unloaded. At least you can then rule out tight chain putting strain on gearbox output shaft.
I'll look that up in the manual. Thanks
05-06-15, 08:35 PM
(This post was last modified: 06-06-15, 09:59 AM by unfazed.)
A simple method to check the the chain is as follows:
Put the bike on the centre stand.
Rotate the rear wheel and find the tightest point of the chain.
At this point push the chain up to the rubber protector at the front of the swinging arm.
It should touch the rubber, if it does not the chain is to tight.
:thumbup
That's great. I'll be checking it in the morning.
Put the bike on the centre stand and looking at the lower part of the chain see if there are any links that are not totally horizontal.
When links seize up they tend to stick at a slight angle which is quite easy to spot.
If you see any it's possible to try and free them up with lube and a pair of pliers, but if there's more than one then chances are your chain might need replacing.
Seized links will be felt through the left footpeg though every time they go round the front sprocket.
The noise could be the chain rubbing on the plastic chain guide as it's position will have been slightly upset on removal of the rear wheel.
Handlebar vibration is something different altogether though, that's not good at all??
More people are born because of alcohol than will ever die from it.
I increased the tyre pressures to 42R and 36F yesterday evening and took it for a short ride. The issue is still there, so I've ruled out tyre pressures at least.
I think the whine is still there at higher speeds, but the vibration is only really felt at around the 20mph mark when I'm slowing to a stop. The whine is most noticeable around 25mph.
I'll have a look round the chain this afternoon and see if the chain is rubbing on the guide, causing the whine and I'll also check the slack on the chain as per the posts above. I'll report back this afternoon.
(06-06-15, 12:34 PM)Big Dogg link Wrote: I increased the tyre pressures to 42R and 36F yesterday evening and took it for a short ride. The issue is still there, so I've ruled out tyre pressures at least.
I think the whine is still there at higher speeds, but the vibration is only really felt at around the 20mph mark when I'm slowing to a stop. The whine is most noticeable around 25mph.
I'll have a look round the chain this afternoon and see if the chain is rubbing on the guide, causing the whine and I'll also check the slack on the chain as per the posts above. I'll report back this afternoon.
You won't see it rubbing, you'll just hear it. It's not a problem as such, just annoying for a while.
Put the bike on the centre stand and spin the rear wheel, if the wheel isn't aligned properly you'll see and hear that it's not right.
It should just be a faint buzzing noise of the chain, rather than any clunking noises as the chain is fighting an incorrect angle of the sprocket.
More people are born because of alcohol than will ever die from it.
So I cleaned and lubed the chain, then loosened it. However, before I loosened the axel nuts or chain adjusters etc, I noticed that the left hand side nut is on the 3rd notch from the front of the bike, whereas the right hand side is past the 4th notch. Is it normal for it to be that far out? Bear in mind that the tyre fitter checked my alignment with a laser tool yesterday afternoon. Would you set the right hand side to the same notch as the left or leave it as-is? I went ahead and loosened the chain a bit anyway, by adjusting the nut on each side by the same amount (moved a quarter of a turn each time). I haven't had a chance to take the bike out a run to see if there is any improvement yet because the weather is mad here at the minute.
imo.marks on the swing arm are pretty accurate. ?..check with a straight edge from wheel to wheel, rest the straight edge on the tyre as high up as possible touching the rear tyre on both sides and then see if its parallel with the front....could be the answer to your whining noise 
One, is never going to be enough.....
An important thing when adjusting the chain is not to have to Axle too loose as this allows the right hand side to move to easily when tightening the axle.
Many tyre fitters do not adjust the chain and put the axle back as they removed it.
It is possible that in the process of removing the wheel the caliper was moved on the unloosened torque arm, then when the wheel was put back on the adjuster would not align as it was as it the wrong place due to the movement of the caliper mount on the torque arm.
The out of alignment sprocket and chain is most likely the cause of the whine.
I took it out a short run there. The whine didn't seem just as bad, though it's very windy out, so it's possible that the increased wind noise just masked it. I also think the vibration felt around the 20mph mark didn't seem just as bad. I think I'm going to loosen the chain a little more tomorrow morning. If the issue is still there after loosening the chain a little more, I'll move the right hand side of the wheel to the same notch as the left hand side and see if improves things.
I agree with Red the alignment marks on the fazer are fairly accurate :thumbup and you would be wise to have both the same.
Out of alignment will cause increased chain, sprocket wear and tyre wear and will also cause the handling to be strange.
In your case it will drop into the left corners quicker than the right ones.
Seems odd that the alignment would be off after the tyre fitter setting my alignment with a laser, no?
Set it with the lazer with loose axle and and then tightened it :eek
Fair point. I'll set the alignment by the marks tomorrow and see if that makes a difference.
The marks on my bike are pretty spot on, i'm sure they're not put there to spoil your day by being inaccurate.
As i said before, a simple spin of the rear wheel should give you a big indication of any misalignment, by noise and by general motion.
In short, if it's wrong it will look and sound shit when spinning, you will definitely know when it's all good.
More people are born because of alcohol than will ever die from it.
Update... I aligned the wheel as per the notches on the swingarm and also loosened the chain to the point where the tightest spot can touch the black rubber thing above the chain and the vibration/whine at around 20mph has gone. Thanks for your help! 
The only problem I have now is vibration through the bars and pegs (more so the pegs) at around 65mph. I'm assuming it's the drive train because it disappears when I pull the clutch in. However, a chap I ride with had a Boxeye Fazer and said his was the same & this is normal for a 600 Fazer. Is this true and nothing to be worried about? The chances are that this issue existed previously, but I've only noticed it recently as I've become a lot more vigilant of how the bike is running since the other problem occurred.
It is common for inline 4 engine to vibrate at a certain section of rev band and it can be made worse by a dry chain.
One old cure Yamaha recommended to reduce the fazer 600 vibration is to place a large washer on the mounting bolt (25-30mm diameter) between the exhaust mount and the footrest
If I know it's normal, I won't worry about it. Though I might try that trick with the washer and see if it improves it.
Thanks
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