Yamaha TRX850 Enthusiasts Forum

wow how high does it feel with the front end droped as well love it feels like my tl did now

i went with suzuki dog bones with 170mm center holes. They cost me $20 from local bike wreckers. So i will have a set off yzf750 one's for sale some time in the next month when they get here from the US good no's when

ive done a few things as well new indercaters front and rear cut the rear mud gard right back new carbon look levers rad gard and new harris grips
before mods

after with new dog bones bikes is sitting a lot higher now

VERY VERY NEAT!!! Much impressed!! Not over-stated yet beautiful.

Neat bike - how much stiffer is the spring rate with the different bones?

dandywarhol wrote:Neat bike - how much stiffer is the spring rate with the different bones?

Not to bad mate it is harder but not cray hard. I only took it for a sort blast around the street and felt real nice . Im going to take it for a ride on friday up the local hills so ill take the c spanner iff it needs ajusting

looks good,,, now when are the bandages coming off ??? they must be all better now ?

DAYS wrote:

dandywarhol wrote:Neat bike - how much stiffer is the spring rate with the different bones?

Not to bad mate it is harder but not cray hard. I only took it for a sort blast around the street and felt real nice . Im going to take it for a ride on friday up the local hills so ill take the c spanner iff it needs ajusting

C spanner will only adjust the ride height - won't affect the spring rate..................................

Just to clarify what you mean by spring rate... Do you mean the actual spring at its no7/maximum adjustment to take 170kg this because of the different length dog bones would be higher because of the spring being compressed further to start to give you the extra height???? correct????

[pedant]Changing the dog bones doesn't affect the spring rate. Changing the spring for one with a different rate does that. Using shorter or longer than standard dog bones affects the rising rate of the linkage. Here endeth the lesson.[/pedant]

Kayla wrote:[pedant]Changing the dog bones doesn't affect the spring rate. Changing the spring for one with a different rate does that. Using shorter or longer than standard dog bones affects the rising rate of the linkage. Here endeth the lesson.[/pedant]

I thought it would as you stretch out the spring from it´s manufactured position with a raised tail??
When i had 40mm raised tail the Ohlin´s shock did not work at it´s best...anyway...

yes exactly.. now you've changed yours Kayla... at 70kg I set mine at 3... to give me the correct sag.. this would effect these ratios kg/adj if the dogbone length changes tho would it not as the spring is compressed to give you the extra height???? correct.. the spring being a linear as such..

ok hang my mistake your stretching the spring to give you the extra height...Why not use a round spacer under the spring to stop the stretch???

cobbadiggabuddyblooo wrote:ok hang my mistake your stretching the spring to give you the extra height...Why not use a round spacer under the spring to stop the stretch???

You're not stretching anything. The unloaded shock is of fixed length, eye-to-eye (assuming a standard shock), regardless of preload setting. The extra ride height at the back comes from using shorter dog bones. The spring's effective rate is changed by using non-standard dog bones but its actual rate remains the same. You're only changing the way the linkage works, not the way the spring works.

AAAAHHHH good onya digga.. Thanks for that.. makes sense...

Kayla wrote:

cobbadiggabuddyblooo wrote:ok hang my mistake your stretching the spring to give you the extra height...Why not use a round spacer under the spring to stop the stretch???

You're not stretching anything. The unloaded shock is of fixed length, eye-to-eye (assuming a standard shock), regardless of preload setting. The extra ride height at the back comes from using shorter dog bones. The spring's effective rate is changed by using non-standard dog bones but its actual rate remains the same. You're only changing the way the linkage works, not the way the spring works.

Bingo.

The spring rate has not changed, but the rising rate of the linkage has changed, or in other words, you have changed the amount of shock movement per cm of vertical rear wheel travel. For example the linkage will allow for say 110mm of wheel travel from a shock with only 45mm of movement (not the real numbers). Changing this ratio will affect the shock's ability to control the movement of the wheel and may even affect the actual amount of wheel travel available (by reducing it).

The result will not be a bike that will have a stiffer spring rate (although it may feel like it), but it will have definitely have a different damping rate. I will be suprised if a fairly substantial correction in damping settings is not required.

Many people make these mods believing it will adjust the weight bias of the bike more towards the front (it doesn't)... the only real change is to the steering geometry, with the head angle becoming a little steeper. Whether it's worth the trade off in reduced rear wheel travel and suspension control will be interesting to hear...especially when a similar effect can be gained by lowering the triple clamps without the trade off in rear suspension travel.

Beau wrote:Many people make these mods believing it will adjust the weight bias of the bike more towards the front (it doesn't).

Are you certain? By dropping the front 20mm and raising the rear 20mm, aren't you essentially rotating the bike about a point and moving the centre of gravity (even if just by a fraction)? Also factor in the effect that riding position will have, if the bike's canted forward it'll put more weight on the riders wrists (and so more weight over the front wheel?). I'm not trying to be argumentative, this is just what I suppose from what my bike feels like now- it's loads better than it was and feels a lot more 'front endy'. I suppose just by junking the standard silencers you shift the weight bias forward anyway.