I've got the whobble ... !

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dave
Cucciolo - the Lil Pup
Posts: 11
Joined: Sun Sep 10, 2006 7:07 am

I've got the whobble ... !

Post by dave »

Hi There,

when i drive with my MHR'83 (complete stock) over 80KM/H and I take the hands of the handle bar, the front end starts whobbling ! :?

what can I do - check or fix :idea:
is this a common problem with beavels :?:

thanks for you help
:arrow: dave
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Craig in France
Paso 906
Posts: 972
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Wobble

Post by Craig in France »

Hi Dave,

Well, handle bar wobble is classically caused by worn or loose head bearings. Other causes can be a worn tire, incorrect pressure, wheel out of balance, wheels out of alignment.

HTH

Craig in UK

P.s No, Bevels do NOT wobble.
Peter Mille
750 SS Greenframe - the holy grail
Posts: 500
Joined: Fri Aug 13, 2004 2:12 am
Location: The Netherlands, Europe.

Post by Peter Mille »

I disagree, bevels DO wobble...!!!
Specialy the later bevels with electric starters, to accomodate the (larger) battery, the frame is weaker around the battery, feel at the tubes, they are halfround!!
The Mille's for example, were notorious for their bad roadholding!
Situation was so bad, no Mille without several frame strengtenings was alowed on the German streets, back in 1984-1986...!!
My Mille ( bought new) would wobble at the most unexpected moments...!
I replaced the frame with a 900SS competition frame from Verlicchi, no more scary roadholding for me!
wrinklygit
Mariana
Posts: 36
Joined: Mon Sep 20, 2004 2:01 pm
Location: Devon,England

wobbly bevel !!,

Post by wrinklygit »

Sorry to dissagree Peter,but my old Darmah with leccy start & a battery the size of a small family house is rock steady at more than the legal speed limit,my money is on headrace problem.Does the wobble become worse or more apparent on deceleration,if so the fault is almost certainly due to play in headrace,Mike.
Peter Mille
750 SS Greenframe - the holy grail
Posts: 500
Joined: Fri Aug 13, 2004 2:12 am
Location: The Netherlands, Europe.

Post by Peter Mille »

The Darmah uses the frame with full round tubes, the later MHR's and S2 (>'82) with electric start uses the bad frame with the halfround tubes around the battery....!
When the HP's went up, ( specialy the stronger Mille) the roadholding gets worse.
dave
Cucciolo - the Lil Pup
Posts: 11
Joined: Sun Sep 10, 2006 7:07 am

Post by dave »

I don't like to read this. :shock:

I thought they changed the frame manufacturers with the milles (as you sad they are really bad). that's what a ducati man told me. anyway.

i already took the bike apart. i saw that the front fork was leaking - needs new seals, tires are old too.

i will mount a steering damper maybe this helps as well.

the wooble feels stronger when decelarating. this was no fun driving - especially with a race bike. :roll:

the bike will be reassembled with a liegme fairing set and upsweep exhaust. i hope this is worth to do it.

i will take special care on front tires, wheel balance, bearings, front fork.

as the bike is now apart - could I strengthen the frame ? are there any plans where to add tubes ?

I will see if i can get it stable.
:arrow: dave
Peter Mille
750 SS Greenframe - the holy grail
Posts: 500
Joined: Fri Aug 13, 2004 2:12 am
Location: The Netherlands, Europe.

Post by Peter Mille »

Dave, not only the Mille, but all bevel twins after 1982 had the weak frame.
With the Mille problems were worse because of the increase of horsepower versus the 900.
Any bevel specialist should know how to strenghten the frame, I know of some German and Dutch dealers who could perform this task, but that's of no use for you.
Consider a new or used frame from an earlier model, like I did.
dave
Cucciolo - the Lil Pup
Posts: 11
Joined: Sun Sep 10, 2006 7:07 am

Post by dave »

Hi Peter,

thanks for your input !

I'll stick with the frame - for now. i was test driving another mhr 84 and the handling was ok. so - there is still some hope.

BTW - i found an 81 frame on ebay for 2250 Euro. too much for now. or what would be the price of such a frame ?

--> dave
Peter Mille
750 SS Greenframe - the holy grail
Posts: 500
Joined: Fri Aug 13, 2004 2:12 am
Location: The Netherlands, Europe.

Post by Peter Mille »

Dave,
The price of a frame depends on many things.
Is it new or used?
Is it a normal or a Verlicchi cromo ( competizione) frame? ( wich I have...!)
Is it a 900SS or Darmah frame ( they are different..!)
Is it a kick or electric start frame
Etc. etc.

I would say, stick with your original frame for now, but have it defenately strengthened by an expert, and have it powder coated afterwards!
There must be a frame expert in England who can do the welding job for you for sure!
Succes.
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Craig in France
Paso 906
Posts: 972
Joined: Tue Mar 23, 2004 3:58 pm
Location: Montpellier, France

Front end wobble

Post by Craig in France »

Hi Dave,

With respect to Peter, I still don't think you should be getting wobble from your 83 MHR. I know the later frame has a reputation of not being so good, especially with the Mille engine, but for several years I had a MHR from the same year as yours and it never wobbled, at any speed, under braking, under acceleration, any time, ever ...

Until you've checked the basics, especially the condition of the head bearings, I wouldn't worry too much about major tasks like frame modifications.

If you're in the UK, talk to Tony Brancato, just outside Oxford (0)1865 891555, http://www.brancatoengineering.freeserve.co.uk/.

HTH

Craig in UK
Peter Mille
750 SS Greenframe - the holy grail
Posts: 500
Joined: Fri Aug 13, 2004 2:12 am
Location: The Netherlands, Europe.

Post by Peter Mille »

What can you espect from a frame with halfround tubes...???
As I said, with avarage speeds and power, it should be OK, but with slightly more horspower and speed, the frame (> '82) is on it limits.
dave
Cucciolo - the Lil Pup
Posts: 11
Joined: Sun Sep 10, 2006 7:07 am

Post by dave »

Hi Boys and Girls,

after finishing my MHR. Fixing the front and rear.

NO MORE WHOBBLE ... so far. Runs straight without touching the handlebars.

And it runs :twisted: !! .... well next step are the carburators. Sometimes running to rich then to lean.

ciao dave
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