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Fork spring rates
Posted: Sun Mar 29, 2009 5:27 pm
by G Beale
Yes it's me again.

I seem to remember a thread on here with a very useful link to a site with various bikes spring rates showing the TRX's forks springs to be very soft (as you all know). If anyone knows where it's gone or even better still can tell me if other forks such as thundercat, late fzr600 (fox eye) etc would have a stronger spring fitted as standard I would be very grateful. I would like to either rebuild my forks using stiffer springs or ideally rebuild a pair from another bike with stiffer springs fitted already which would mean less down time for my baby.

At 14 stone my standard front suspension is a little bit over worked to put it mildly. Thundercat & fzr are the only forks I know of which are a straight swap unless anyone can tell me otherwise ?
Re: Fork spring rates
Posted: Mon Mar 30, 2009 9:40 am
by idl1975
G Beale wrote:Yes it's me again.

I seem to remember a thread on here with a very useful link to a site with various bikes spring rates showing the TRX's forks springs to be very soft (as you all know). If anyone knows where it's gone or even better still can tell me if other forks such as thundercat, late fzr600 (fox eye) etc would have a stronger spring fitted as standard I would be very grateful. I would like to either rebuild my forks using stiffer springs or ideally rebuild a pair from another bike with stiffer springs fitted already which would mean less down time for my baby.

At 14 stone my standard front suspension is a little bit over worked to put it mildly. Thundercat & fzr are the only forks I know of which are a straight swap unless anyone can tell me otherwise ?
It's racetech - the US suspension people. TRX stock they say is .500kg/mm, versus .78kg/mm for stock YZF750R, versus probably 0.9kgmm or more they would recommend for you. Just find the suspension products picker, and it will list all products available for the TRX, which shows oil weight and spring rate for the stock bike.
Edit - they will have FZR and YZF listings as well of course. Note that I _believe_ however that these may not be the right models. IIRC, FZR600 (as we knew it) didn't exist in the US - it was basically an FZ600 or something similar and very primitive, which only expired once the US got the R6, probably in about 1999. And again IIRC they never got the Chunderblat.
Basically, Yamaha USA were marketing to club racers, Star Boyz fans and "O.G. style" bling merchants who wanted something flash they could coat with chrome. They left the quotidian utility-bike market to Honda, so instead of a Blundertwat, you had to buy a CBR600 F3.
Re: Fork spring rates
Posted: Mon Mar 30, 2009 9:56 am
by Mincehead
Is their some dislike of Thundercats around here?
Or is it simply that they`re not TRX`s?
I`m always told by anyone who`s owned one,what a fantastic little bike they are.
The fairings are especially good and they`re rock solid at speed,quite underrated I thought.
Re: Fork spring rates
Posted: Mon Mar 30, 2009 10:23 am
by G Beale
Thank you so much idl1975 I scanned every page of this forum last night but still couldn't find a mention. At least now I can find racetech on't internet.
I think the thundercat gets some stick for the name (kids cartoon remember it ?) & the fact they looked a bit odd ? Mate of mine had one way back & to this day swears by it ! I nearly bought 1 before the TRX with a different fairing/headlight assembly which was/is the only thing I don't like about the standard ones.

Re: Fork spring rates
Posted: Mon Mar 30, 2009 10:29 am
by idl1975
I bought one new in 1996.

They just have a name which is amenable to jolly japes. The engine is fantastic, that much is certainly true.
Yamaha didn't take the two sports tourers very seriously themselves. The reskinned EXUP, after all, features the words A.S.S. in big letters on the tail unit.

And it's called a thundercat. As in "Thundercats" with animated cat people waving swords. I mean really.
Mincehead wrote:Is their some dislike of Thundercats around here?
Or is it simply that they`re not TRX`s?
I`m always told by anyone who`s owned one,what a fantastic little bike they are.
The fairings are especially good and they`re rock solid at speed,quite underrated I thought.
Re: Fork spring rates
Posted: Mon Mar 30, 2009 10:40 am
by cobbadiggabuddyblooo
Weighing in at 76kg (11 stone???) myself the chart recommended.95kg springs for myself at street sports/race spec...... so with yourself at 14 stone mmmmm.. maybe for std road/touring use... these were with linear springs as such. Did you read the interesting articles on the effects on dampening ect with progressive springs

Re: Fork spring rates
Posted: Mon Mar 30, 2009 11:15 am
by Mincehead
Kids cartoons?
Blimey,I must be getting old,or spend too many hours working and tinkering with bikes to be anywhere near the radiation box,never heard of them!
So just as I thought,another Yamaha gem after all,cheers guys.
