Anyone played with the suspension arm positioning?

[Kayla]

Are the holes further back, towards the rear tyre, than the standard holes? I can't remember. Anyway, surely if you move the linkage back, it'll make the whole rear end rotate about the swingarm pivot and drop the rear, increase rake and reduce trail and make it look like it's dragging its bum

[Kevtrx849]

Exactly Kayla, was never going to be an option. About the centre stand theory, my mechanic mate worked at a bike wreckers and he'd seen similar setups on various bikes that had been utilised for centre stands. No specific Yamaha models were named.

[WR450FGreg]

.

I did ask a mechanic mate many moons ago about the spare holes and if they were an alternate mount for the suspension. He reckoned they were used on another model as center stand mounts. TRX being a parts bin bike, that sounded like a plausible idea.

Yeah, I guess that's a possibility.
But don't centrestands usually attach to the frame?

I'm becoming more and more intrigued by this un-utilised mounting position.

I may just investigate/try it in a few weeks when I'm on holiday and report back here!

Greg

[Kayla]

Has anyone got a decent photo of the underneath of the bike where the holes are? It should be blatantly obvious what the effect of moving the bell crank to there would be just by looking at it

hang on-



That's a pic of my bike. Ignore the swingarm and shock and all that gubbins, you can see that if you were to move the bell crank backwards the rear of the bike would drop like a stone. The holes are most likely to be from when the castings were machined in a jig at the factory.

edit- I miss that bike

[Mincehead]

Yes Kayla that`s my belief too, the hole would have been utilised for the jig used to position, hold and machine the casting at the point of manufacture.

[Dav]

heh heh...bell crank

[WR450FGreg]

.
Ok, I actually got out to the bike today and had a look at my TRX links instead of relying on memory........

The alternative mounting point is on the frame, not the swingarm!

I've never thought about rear linkage/arm lengths before, only fork protrusions and shock lengths, I find this all quite interesting!

I'm sort of shying away even more from the centrestand theory now, because the link arm would hit any bolt there if both mounting points were used for whatever reason/s.

I wonder if the TDM850 or some other Yamaha has the same swingarm, but different suspension arms? It may need that rear mounting position.

[Mincehead]

That H casting is only on the TRX, it`s got to be for jigging purposes when the casting was machined at point of manufacture.

[Kayla]

I have no intention of changing anything on the bike, it handles just fine like it is!

That's because either you or a previous owner has fitted YZF750 dogbones, which are 10mm shorter than the TRX ones which gives around +35mm lift at the wheel spindle. But you'd know that-

BTW, I'm a former roadracer, I know a bit about frame geometry changes. I was being polite/modest when originally asking how it will affect the bike.

I'm sort of shying away even more from the centrestand theory now

Thanks for letting us know

Tell you what, instead of taking advice from those on here who have owned TRXs for ages and have made the mistakes you're about to make, and done the stuff you're about to do, just ask a load of questions then get all uppity when someone dares to try and stop you wasting your time.

[alextrx850]

I reackon that you should support the machine..pull the linkage back into the spot ..drop the bike back onto its wheels , and then take a distance photo of the result...capiche.!

[WR450FGreg]

.

just ask a load of questions then get all uppity when someone dares to try and stop you wasting your time.

Oh my God! (rolls eyes) What ARE you on about? LOL!!! (Shakes head in disbelief with huge grin on face.)
Settle petal!! .... its all good!
Comments are often taken out of context on the internet, I've done it many times myself and clearly you're doing it now! (NB: That's a SMILE I just put in there, a genuine, happy smile.)

For the record, once and for-all ..... I have no intention of changing anything on this bike, never have, never will, it handles just fine and after all .....it's just a f......g roadbike!!!! (Jeez Louise!)
I was curious about what the extra mounting point was for, that's all!!
I may see if the link fits the rear hole and measure the difference in seat height in the next few weeks, but then again I may not too. Whatever the result it will be going back the way it is now.

That's because either you or a previous owner has fitted YZF750 dogbones, which are 10mm shorter than the TRX ones which gives around +35mm lift at the wheel spindle.

Man, the bike is as bought from Yamaha Australia by a good mate of mine. I bought it from him and haven't changed a thing except the engine oil and filter.

But you'd know that

Huh?

[WR450FGreg]

.

I reackon that you should support the machine..pull the linkage back into the spot ..drop the bike back onto its wheels , and then take a distance photo of the result...capiche.!

alextrx850,
Yeah, if I do end up trying anything then that's just probably all I'll do mate.
I'll post before and after shots here for reference.

(I'm beginning to wish I'd never asked the question originally now, LOL!)

[cobbadiggabuddyblooo]

Don't forget now to take the film crew and ride it at 200kph into a brick wall and post it on Aust. funniest home video with the caption I knew i shouldn't have moved that suspension linkage
Just wear a big moe and orange overalls with Leo wanker on them and have the pit crew hit you with fire extinishers
I'm sure you'll come out smiling he always did

[cobbadiggabuddyblooo]

sorry i couldn't help but take the piss... but it's got all the hallmark traits for a great comedy skit..Maybe Fawlty mechanics.... Just don't mention the war

[fung]

.
Ok, I actually got out to the bike today and had a look at my TRX links instead of relying on memory........

The alternative mounting point is on the frame, not the swingarm!

I've never thought about rear linkage/arm lengths before, only fork protrusions and shock lengths, I find this all quite interesting!

I'm sort of shying away even more from the centrestand theory now, because the link arm would hit any bolt there if both mounting points were used for whatever reason/s.

I wonder if the TDM850 or some other Yamaha has the same swingarm, but different suspension arms? It may need that rear mounting position.

So I checked the std dogbones i took off my australia sold TRX and the markings 4fm-10 are present.
i guess if your bikes forks are set to 18.5mm protrusion above the clipons, and you have a std TRX shock, then the bike is in std aussie trim.
to get the TRX to its sweet spot without too much drama, raise the forks thru another 15mm and change the dogbones for a set to raise the rear by 20mm (available from kayla among others).these can be bought from various sources.
this increases the bikes turn in feel and doesn't decrease the ground clearance (up in the back=down in the front).
should you suffer from wrist pain, you can use tubular spacers under the clipons to raise them back up the 15mm, or if you want to as some have, the bars can be swapped left to right and inverted making them flatter.
good luck,
cheers
fung