MM TYRE HELL

[SKIPSTER]

Okay, any input appreciated.

4k miles and the original tyres needed replacing. (I seem to recall they might have been MICHILINS but can't be sure)
Seeking more milage for my buck I opted for Bridgestone BT 023'S
The return journey, partly on private roads, when accelerating revealed a 90mph weave from the front end.
Back to bike shop.
Balance check and head stock check.
Head stock loose, off to Bahnstormers who where apparantly far to busy to fit me in, but give them there due, they did inspect the bike and told me the head bearing needed replacing.
So off I went to Vines in Guildford. Well I know for a fact these guys where at the time seriously under pressure due to the workshop being so busy, but the Head man was brilliant enough to queeze my bike, 1/2 an hour later, head stock tightened, problem solved.
On the way home, same problem, front weave and the bars come alive and waggle from side to side, but only from 90MPH PLUS.
Back to the tyre shop.
Wheel out, duplicate replacement thinking it might be a one off 'duffa'
Off I go to check.
Same problem.
Back to the tyre shop.
He suggested the sports touring tyre dosn't suit the bike.
On go two sport BT 016 Pro's
Off I go.
Same issue, but not as bad.
To top it all I collect a two inch nail in the rear tyre,
So for the time being i'm frustrated by a MM that won't let me ride in a straight line when giving it the berries.
When I have time I will check the suspension settings, as I seem to recall the front end has been dropped by the previous owner.

So to conclude has anyone else experienced similar or can you recommend a solution.. Thanks.

 

[edzt]

I take it you didn't have a problem 'till you swapped rubber?

 

[SKIPSTER]

..nope, stable and not a flutter from the bars up to 130...

 

[stevemersey]

I would look to that lower front. Will have reduced your trail and reduced stability. A change to a tyre with a more flexible wall or different profile could just show it up.

 

[SKIPSTER]

I compared my forks/yokes with the Nutty Professor's MM this evening, both identical so will check preload etc over the weekend.
The tyre profile appears much more rounded that my old Michilin front, and the tyre feels as though it is over inflated and rock hard, (even though it isnt).
A wise man (cough) told me any issues with the back end ( so to speak) can transfer through to the front, I wonder if there is any truth in that?.
I might stick the Nutty Professor's worn out front on mine when he's finished with it and see if that remedies the problem.

 

[James Bryan]

Not tried the 023s, but have had two sets of 016Pros

The BTs caused me no problems, other than both rears lasting less than three thousand miles.

Your "wise man" could well be right, (on both occasions on which I've collected iron ware in my rear tyre, I felt the front go "off"), so it would be worth checking at the other end.

And, I would think that the dropped yokes will not be an issue, (beyond making the side stand a bugger to release on adverse camber), as I'm a founder member of the short-arsed supporters group & have the forks dropped to the lowest recommended setting.

Best of luck in sorting this, and I'll be interested to hear the eventual outcome.

All the best, Jim.

 

[Nutty]

I'm stumped on the tyre problem, but it was good to meet up last night, and have a blast round the fine roads of West Sussex.

You still need to get rid of the screen and engine bars

 

[SKIPSTER]

....your a fan of my screen I can tell Bud, perhaps you could fit a screen on the back of your bike, then the rear of your helmet won't get splattered in flies when they over take you mate

 

[DrFarkoff]

What tyre pressures are you running ?

32F 36R?

If so try 36 F 42R as per Bridgestone site

I had a problem with a bike a while ago and tyre pressure was the issue mind you with it it was change of direction that annoyed it Rather than hard acceleration

 

[SKIPSTER]

...ahaaaa, so James Brian has used these Bridgestones with out issue. I'm pleased about that.

It's very strange that a simple tyre change would have such an adverse effect.

The smallest road imperfection sets it off when going at any considerable speed.

 

[Nutty]

....your a fan of my screen I can tell Bud, perhaps you could fit a screen on the back of your bike, then the rear of your helmet won't get splattered in flies when they over take you mate

 

[SKIPSTER]

Latest update. I have tried various tyre pressures to know avail.
It's a wee bit to early to confirm, but I think I'm noticing an improvement and less weave. I think as the front tyre profile is starting to wear more on the sides and become a touch more triangular, perhaps this is improving things.
A black art for sure and ive decided to shag the tyres as quickly as possible and live with the issue. It sure makes for a more involving riding experience!

 

[Joe Bar]

Latest update. I have tried various tyre pressures to know avail.

Sorry, just spotted this when reading your for sale ad, and wondered about your tyre comments, so had a search.

My MM had the dreaded weave from new and I could get it accelerating hard off corners from anything between 60-120 mph, with the bars oscillating pretty badly. The bike was on Michelins from new, and at the time could find very little info on it. As I had a trip to the Alps planned I was almost at the point of buying a steering damper from the US to try and sort it.

Instead I went out with the spanners and screwdriver and spent a couple of hours riding the same piece of road and twiddled with the suspension settings bit by bit until I pretty much dialled it all out. Transformed the bike and had no problem flat out on the autobahn.

From memory I cannot recall where I ended up on the settings, but they were definitely softer rather than firmer.

 

[litelfun]

Hallo ,
I use Conti roadatacks they was on when I got the bicke I am luckey if I get 2800 km aut of a back and 4500 on a front but thats good compaired to what I used to get aut of my uther sms licke ktm 660 or huski 570 only around 900km



compair

Okay, any input appreciated.

4k miles and the original tyres needed replacing. (I seem to recall they might have been MICHILINS but can't be sure)
Seeking more milage for my buck I opted for Bridgestone BT 023'S
The return journey, partly on private roads, when accelerating revealed a 90mph weave from the front end.
Back to bike shop.
Balance check and head stock check.
Head stock loose, off to Bahnstormers who where apparantly far to busy to fit me in, but give them there due, they did inspect the bike and told me the head bearing needed replacing.
So off I went to Vines in Guildford. Well I know for a fact these guys where at the time seriously under pressure due to the workshop being so busy, but the Head man was brilliant enough to queeze my bike, 1/2 an hour later, head stock tightened, problem solved.
On the way home, same problem, front weave and the bars come alive and waggle from side to side, but only from 90MPH PLUS.
Back to the tyre shop.
Wheel out, duplicate replacement thinking it might be a one off 'duffa'
Off I go to check.
Same problem.
Back to the tyre shop.
He suggested the sports touring tyre dosn't suit the bike.
On go two sport BT 016 Pro's
Off I go.
Same issue, but not as bad.
To top it all I collect a two inch nail in the rear tyre,
So for the time being i'm frustrated by a MM that won't let me ride in a straight line when giving it the berries.
When I have time I will check the suspension settings, as I seem to recall the front end has been dropped by the previous owner.

So to conclude has anyone else experienced similar or can you recommend a solution.. Thanks.

 

[Mav]

What about the fact that you have that rather large screen fitted? Any chance it's simply turbulence at high speed? Pretty easy to confirm...

 

[Nutty]

What about the fact that you have that rather large screen fitted? Any chance it's simply turbulence at high speed? Pretty easy to confirm...

That screen's got a lot to answer for!

 

[Joe Bar]

The fact that the screen was already fitted before the tyres were changed, would suggest that it is not the cause. I do believe the problem can be resolved via re-setting the suspension to suit the new tyres. A notepad and pen, screwdriver and a couple of spanners is all it takes, and adjusting the suspension costs nothing, and can easily be re-set if it doesn't work. Nothing to lose by giving it a go, but everything to gain.

 

[SKIPSTER]

Oi Nutty, you can get counselling for screen envy
........
....... and don't ignore your wind deflector issues,

 

[Nutty]

Oi Nutty, you can get counselling for screen envy
........
....... and don't ignore your wind deflector issues,

Thought you'd like that!

 

[SKIPSTER]

Cheers Joe B. I agree, no issues until i changed the hoops.
I might have a whirl at the suspension today.
Interestingly I went to a bike meet last night and had a car dealer want to put the MM on a plinth to sell in his Porsche dealershop, the deal seemed more than reasonable, but for many reasons I really enjoy the bike and am reluctant to sell. It gives my old GSA (which i miss) a run for its money as far as being an appropriate bike for my needs, but the MM has the added coolness of rarity, better looks, so much lighter and a stonking engine. It might even hold or go up in value.