Author Topic: Triumph Weave  (Read 5691 times)

Offline mikeyT110

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Triumph Weave
« on: May 09, 2011, 11:11:11 AM »
1958 T110, completely refurbished, and with adjustable front dampers.

Over 45-50mph gently, over 60mph it weaves a bit more.
Not each time, but most times.

When it does not weave, I can start it weaving by moving around in the saddle, as I found out last weekend during some hard motoring up to Devil's Bridge.
Disconcerting yes, possibly potentially dangerous, Hmm!!, annoying certainly,   >:(

Does anyone know the cause and the cure.  :-\

Cheers. Mikey

Offline R

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Re: Triumph Weave
« Reply #1 on: May 09, 2011, 11:48:26 AM »
"with adjustable front dampers"

There are a multitude of possible different causes of a weave.
Tyres, forks, steering bearings, rear shocks, tight chain, loose engine mounts.
Large flappy sleeves on your jacket.....

You mention adjustable front dampers.
How does this work ?

What is the condition of  the rear shocks ?
What tyres are fitted ?
How tight are your chains. And condition and roundness of the sprockets ?
Primary chain correct adjusted, oiled, and gearbox solidly bolted in place ?

Offline rogerwilko

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Re: Triumph Weave
« Reply #2 on: May 09, 2011, 11:57:37 PM »
Disconnect the steering damper, then check.

Offline bikerbob

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Re: Triumph Weave
« Reply #3 on: May 10, 2011, 12:22:26 PM »
You say completely refurbished so everything is either new or reconditioned which leaves something you  have maybe taken for granted I would suggest that you first check that the wheels are correctly aligned as this is a common  thing that can cause steering problems. Triumphs of that period were never very good at roadholding the engine was just to powerful for the frame I am not sure if that year they still had the single down tube things did improve when they had the twin downtubes. Typical for the period Triumph great engines poor frames Nortons great frames not so good engines, that's why you got so many Tritons.

wetdog

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Re: Triumph Weave
« Reply #4 on: May 13, 2011, 02:41:50 PM »
my Thunderbird also 58 did this and drove me mad , changed head races to tapper bearings and it helpped a lot but was never a great handler , looking  at the swing arm mounting and im not surprised at the handeling

Offline rogerwilko

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Re: Triumph Weave
« Reply #5 on: May 13, 2011, 11:14:51 PM »
They wouldn't have been that bad from the factory. Jack up the front of the bike and turn your bars side to side and check fo roughness or resistance.

Offline filthyphil

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Re: Triumph Weave
« Reply #6 on: May 25, 2011, 02:52:10 PM »
New swingarm bushings? No lateral play when you hold the bike still and apply sideways force to the swingarm?
That or the friction damper or steeing head bearings seem the likely culprits. And how about the tyre choice? I think an Avon SM rear and Speedmaster front would have been the original fitting - K70s might be a suitable tyre these days, but TT100s could upset the handling, being a knife-edge kind of profile.
And I agree with wetdog - the swingarm support engineering is a really poorly thought out system - Malcolm Uphill must have been a very brave man.....tight fitting and tight bolts for those rear frame plates would be essential to getting good handling.
cheers

Offline Welsh Wizard

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Re: Triumph Weave
« Reply #7 on: May 25, 2011, 11:18:40 PM »
Season Category Starts 1st 2nd 3rd Tot. Poles Bike Points Pos.
1970 350cc 1 0 0 0 0 0 Padgett Yamaha 8 22
1970 250cc 1 0 0 0 0 0 Suzuki 3 38
1969 500cc 1 0 0 1 1 0 Norton 10 26
1968 250cc 2 0 0 0 0 0 Suzuki 5 9

Seem to remember
1968 Malcolm ran a 250 Suzuki ,1969 it was a 500 Norton,1970 250 Suzuki and a 350 Padget Yamaha ( http://www.motogp.com/en/riders/Malcolm+Uphill )


As for his career Malcolm started by financing his own Norton which he prepped himself, seem to remember Malcolm told me it was in his shed in the back garden
 
I know he told me at one time he was teemed with Percy Tate on a Thruxton 650 Trumpy  http://www.flickr.com/photos/michael_bellee/4363640270/ 
http://www.flickr.com/photos/michael_bellee/4363640274/in/photostream/ but I am sure that was either 69 or 70 and his average speed was some where about80 to 85 MPH

His best year at the TT was 1970 when he won the proddy 750cc TT at an average speed of 97.71mph 

1970 he came 4th on a Yamaha 350 in the Junior 350 TT at an average speed of 95.55mph
that same year
 
[Selwyn Griffiths rode a Matchless 500 to 7th place in the 500 TT seniors at an average speed of 93.54 ( what you have to ask was when was the last 500 Matchless made, so probably no factory backing for him)]

I do remember while at the Ponthir M/C club years ago Malcolm stating that the frame on the Trumpy was inferior to the Norton and why did they not use the BSA frame which was full duplex as they did with the OIL frame lightnings and Bonnies. He did defend the road holding of the Trumpy frame as I was giving him some stick, myself being a Norton and BSA owner at the time. he did concede that the Trumpy frame could have been better but if all was tight and every thing was in good condition such as swing arm bushes, wheel bearings, and the shocks well top with oil and working good they were stable on the road except about 85mph when you had a band that gave rise to a slight steering wobble but as long as you were powering through it , it was no major and when slowing it never seemed to appear.

Since then I have added some trumpies to the stable mainly T100c, T100rr, 6T, T120 oil in frame, T160, with the exception of the T120 I have noticed the wobble that Malcolm talked about on all of them, and I can also say that the BSA unit rocket I have also has a head shake at 80 to 85mph, so it would seem that it has some thing to do with steering geometry as yours kicks in earlier than both the known wobble speed it would suggest something is worn and allowing it to occur at lower speeds,  so first check the swing arm for play, make sure the frame is sitting right height look for the forks sitting low and the rear shocks sitting the bike high. check you steering head bearings for play or being over tightened, make sure the steering damper adjust smoothly ( an area often forgotten about, as they should adjust smoothly and not in fits and starts of being too lose or or to tight.)