I first noticed this happened a few times when I was out with the Essex branch visiting Canvey the other week. Then forgot about it, then experienced it just the once yesterday. Happens in the lower gears, at lower speeds - 10/15 mph maybe, and only when I’m treading the brake pedal. I hear/feel a slight graunch - probably from the mid/back of the bike, down below somewhere. Only very briefly, but kind of sinister. Bike has around a genuine 60k miles under it. Initial thoughts - angle of the swinging arm changing enough to upset the UJ or somewhere in the suspension? But would also then be noticeable over bumps? Rear brake pads vibrating? Drive box moaning on deceleration?
I don’t think it does anything at other times. Other notes - UJ was refurbed by Nigel at NBS only maybe around 8k mikes ago. Also around that time he did the seals on the drive box, and reported the internals looked in good shape. S/Arm bearings were swapped out at around 50k and were fine last time I looked. Haven’t got time to look right now, and the old things probably going to be dragging my corpulent ass up to the Clocks Forward in a couple of weeks. Did notice I’d forgotten to retax from the start of this month - maybe some DVLA aversion device?
I’ve certainly only noticed it so far when I apply the brakes with the pedal, and at low speed. My discs are in a pretty shocking state to be honest, but I don’t think it’s that. The callipers have long since had the nasty chromed pistons swapped out for the later non stick type so I don’t think it’s that - and also the bike has seen a lot of use in the last couple of months.
Probably best I check the pads back there and make sure there’s still some oil in the rear box before I set out for that one.
check the easy things first, starting with the brakes, dont know about where you live but up my way the roads are still heavy with road salt etc which gets everywhere, including aroud the brake area, I would also check all mudguard bolts and number plate bracket bolts, very unlikly to be those items but it will help to narrow down the possible cause. ( and costs nowt)
if nothing found then for your peace of mind I would whip the swinging arm off and check the UJ, the problem with small block v-twins is if the u-j has gone it can damage the gear box end cover if not sorted out asap, and these covers are not easy to find second hand,
when mine went about 15 years ago it was a problem getting a replacement, so it would be even more so these days
. the u-j’s on bigger bikes like the late 1970’s Le-Mans, 850T3’s etc were no problem, just remove the uj, centre punch it, apply Loctite and get another few thousand miles out of it, but not so the small blocks,
i filed a sliver of paint of each side of the new brake pads on mine to make the pads a slightly looser fit in the caliper and that solved most of the problems with my brakes unless the disks rust when stored for a while
I think it’s this. Bit of vibration when pedal first depressed. Sometimes pads/shoes can make odd noises, you are only hearing it at slow speeds because it’s otherwise drowned out by wind noise etc. But yes I would look at the rear pads just to be sure everything’s OK. As regards transmission, turning the rear wheel by hand should show up anything untoward?
Brake pads in the front of my Bonneville (a 750 '79) used to shriek like a banshee. I used to routinely paint some weird blue gunk (specific to the purpose) onto the backs of the pads on that fairly routinely which was an effective if not long term fix. My graunch feels more sinister, even more gut wrenching somehow than that. I did give the rear calliper a quick shake as I was pulling my station bicycle out of the garage this morning lest it were loose. Felt tight â€“ hah, by hand. Noted I have stainless bolts holding that, and the front callipers on. My work there and I do know that folks generally stick to the 8.8s on these applications.
Guess I ought to pull the calliper off and have a good sniff around out there before I go any great distance. Maybe I should allow an hour or two and pull out the s/arm as well and check the pivot bearing and UJ at the same time dammit. BTW â€“ rode out to Le Mans two up with all the gear on on this bike when the s/arm bearings were on the way out last time. That made for a wayward ride. Squirrely I think they call it.
Well, with band practice postponed yesterday evening due to the drummer going AWOL I figured Iâ€™d use the time to stick the Veefer up on the table and pull the rear end. From that I can report:
. Drive box oil was slightly low, but not bad. No mayo in there.
. Gearbox oil was on the button. This despite oil over the back of the box plus any amount of dirt sticking to it.
This comes from the overly worn shift shaft and housing.
. Engine oil is well up the stick.
. The rear calliper was firmly affixed
. Brake pads were in good shape, probably about half worn
. Both pistons moving freely in the calliper
. One swing arm bearing has suffered water ingress and is rough (dammit), but it is surely not that
. UJ is smooth and nice.
. All splines show some wear but nothing serious
. Rear box turns smoothly
. G/box turns smoothly from the shaft, when in neutral
. Wheel bearings OK
. No untoward signs of scuffing anywhere
So Iâ€™ve buttoned it all back up. I guess Iâ€™ll have to see how things progress. Of course I inevitably found other issues. Now reporting under their own headings. Hmmmm.