Triumphrat

Armen

Anyone do a 520 chain conversion? Seems with an alloy rear sprocket a bit of weight might be saved. Brands? Experiences?
Did a simmilar deal on my SV650 and saved a pound or so.
thanks,
-Armen

B02S4

Going from 525 to 520 on one of these bikes is much-ado, IMO. I did a 520 conversion with an alloy rear sprocket (15/47) on my S4 & liked it. But I personally wouldn't bother with it on a Bonnie twin. Any Bonnie twin.

Forchetto

In theory you'd be reducing the robustness of your final drive, but that can be avoided by selecting a quality 520 chain with a high tensile strength figure.

Advantages of reducing chain and sprocket weight include the reduction of both unsprung and rotating weight, so it has the same effect as increasing an engine’s torque output, that is, it makes it easier to accelerate the bike and also gives the rear suspension an easier life.

If you look at this chart you'll see under "premium xw ring chains" a 520 size with very nearly the same tensile strength as the 525 in the same range and considerably higher than lower quality ones further up the chart.

twinfan

if anybody of you guys having too much money for crap which is absolutely unnecessary on these bikes...


i can give you my bankaccount, to send some money





twinfan

Armen

As for the waste of time and money arguement, consider this-when I did the same conversion on my SV650 (with alumium sprocket) it saved 1-1/2 lbs of mostly unsprung weight. Most racers and serious street/track riders would give their left nut for that kind of reduction. Whats more, the aftermarket parts were about half the cost of the OEM stuff.
I guess I should start my posts with "I'm not asking permission or telling you you have to do this."
As was pointed out, the high end 520 chains are more than strong enough.
While I was at it on the SV, I made aluminum wheel spacers to replace the steel stuff, bought a wave rotor (only $125 with new pads), and swapped to a lighter tire (Michelin Pilot Power). Net savings-over 4 1/2 lbs for not much cost. Rear suspension definitely tracked better.

rodburner

Nice job Armen.I personally went "up" to a 530 because of my extended swing arm,but with the aluminum Talon 43T out back,my net weight gain was only a pound or so.

__________________
Ruining a perfectly good Bonnie since 2004.

twinfan

did you do 2D datarecording?


i bet there is no "feelable" difference...i made all that stuff on my 675 racebike...saving 1kg...there is no feelable difference from 525 to 520

on those twins nobody really needs it...or are you racing?


which chain did you use? i never saw a racingchain like DID ERV 3 for half the price like VM

maybe you go chainshopping @ your local triumph dealer...but then i have to say you didn´t do your homework

Armen

Hey Rodburner,
How did you do the longer swingarm-and why?

Twinfan,
As I said 'compared to the OEM prices."
As for the weight difference, it all adds up. I got roughly 4 1/2 lbs off the rear wheel. Even my uncalibrated butt shock dyno could feel a difference.
Oh, did I mention I gun drilled the axle, used Ti nuts on the sprockets, gun drilled the sprocket studs, and widowed the brake caliper carrier? Not kidding.



Not sure why anyone would pass up on the chance to drop some ass end weight. Especially if the chain and sprockets need replacing.

Again, I'm not asking permission : )

rodburner

[QUOTE=Armen;1517294]Hey Rodburner,
How did you do the longer swingarm-and why?

2 factory arms pieced together,to slow down the steering a little,lower the bike a lot and give me room for various experiments..
And you're right,shedding a pound or 50 is a good thing.

__________________
Ruining a perfectly good Bonnie since 2004.

Armen

So, is the rear shock direct or linkage? If it is linkage, did you cannibalize another bike or make your own bits?
Very cool : )