juddering at speed VFR750 1995

Hi Peeps just joined the forum.
I recently acquired a VFR 750 1995 runs fine but when up to speed on the ahem ! German autobahns at around 90 mph i get a worrying judder/ vibration on the bike
i had the front wheel balanced ,replaced the bearings ,checked the headstock but its still there, any ideas as to why this might be ? never experienced this on any bikes i have had previously (and there has been many ) Cheers
andy .

 

Steering head bearing bad maybe?

 

i did remove them . loose bearings were in there ,regreased and refitted . made no difference of course .

 

How the tyre looking physically? No bulges or other distortions?

How about the fork bushings, is there any detectable play in these?

 

you didn't mention balancing the rear wheel ? a really bad chain can do weird things at speed, so check that.

how many miles or kms on your bike ? greased or not most headset bearings need replacement by about 35-40,000 miles.

 

Loosen your grip on the bars. Sometimes riders just grip too firmly.

 

I have a similar issue that started on my 5th gen recently, tyres are good, had the head bearings replaced last year and grabbing the front wheel I can't find any play in the wheel bearings, bike was fine until recently, can notice this at 30 mph cornering, feels like the front wheel is loose or something, very weird.

 

The tyres look ok ,not very worn no apparent play either .

 

Yeah i have not touched the rear at all , was wondering if it could be rear wheel balance /bearings or both, 37000 + miles

 

those bearings are usually ok at that mileage, so that leaves the wheel balance in question. not all shops can do it.

get the rear up and start investigating, ladddie.

 

Turns out to have been the back tyre all along , no idea why but new conti's on and its a different bike .

 

Thanks Andy for making time to report how the problem was solved.

Feedback on how things are resolved is so important to making this Forum a useful resource for others who may have similar problems. Sadly too often threads get started and receive advice but once the bike is fixed we never get told how.

I had the feeling that even if the tyres were not very worn, they might simply be too old, which creates an increased risk of internal damage or even separation to reinforcing bands within the tyre carcass. This would allow the tyres to look and perform passably at low speeds but could result in dangerous bulges forming especially at Autobahn speeds! So whenever I buy a used vehicle I make sure to check the date codes printed on the tyres - there are loads of websites which show you how to decode the information.

I am guessing the old tyres have been disposed of already. It would have been interesting to know the brand or date codes on the tyres you just replaced.

Anyway assuming your 750 is now on the road, please find time to take some photos and head over to the introductions part of the forum and say Hi to the rest of the folks on here and tell us a bit about your "many" bike history.

Then I suggest you get out on your VFR before the weather or another COVID lockdown brings an end to riding this year.


Take care ATGATT




SkiMad

 

Tyres were bridgestone's bt but were about 5 year old , would like to post pics but i have started to strip down and mint it up a bit, i have a ZZR for the winter

 

I had a badly balanced rear tyre a long time ago, I felt a vibration under my arse at highway speeds (I did not install tyre - had to mention that.) Got it taken care of and problem solved.

These bikes, (or at least mine) are sensitive to tyre ware, I notice they get scalloped as they wear. New rubber is a revelation all the time.