Yamaha TRX850 Enthusiasts Forum

Having a bit of trouble finding online sources for TRX sprockets in other than the standard sizes. Or more precisely, a 16t front and a 39t alloy rear.
Easy enough to find standard sizes and/or a set of steel sprockets, but a bit harder to find anyone listing non-standard sizes.

Can anyone suggest a good supplier in the UK?

Also, does anyone think a basic 'o' ring 525 chain with a 8400lb tensile strength is inadequate for a 79hp TRX? I would have thought it would do fine, but would be interested in hearing any opinions.

Daft question- have you tried B&C Express? They can normally machine one up from their stock of blanks pretty easily. I've not used them for TRX stuff yet mind, just TZR250 bits.

as above B&C express will have all you want

steve speed wrote:as above B&C express will have all you want

Thanks guys - they don't list the TRX items on their website if I recall, but from the sounds of it they will be able to sort me out over the phone just fine.

they only list bikes that are currant production ,,but they will sort the trx

B&C are probably best as said, but can also try www.biketorqueracing.co.uk who are distributors in UK for Afam.

+1 for B&C

Why 16/39 - more options with 17/42

phuk72 wrote:+1 for B&C

Why 16/39 - more options with 17/42

Thanks for the advice.

I currently run 17 / 43 with steel sprockets. I like the ratio (130mph theoretical top speed is more than enough; lots more thrust), but am thinking it would be a good idea to replace the chain & sprockets because the bike was stored for 8 years with the current chain on it. I've been thinking that when replacing everything it would be a good idea to minimise the mass of the components. Hence I wanted to go with a smaller steel front and smaller alloy rear, which will also let me use a 110 link chain instead of 112. 16/39 raises the gearing a bit (135 mph theoretically, which I believe is closer to what a stock TRX can actually pull anyway, with a downhill slope and following wind...), but it's still lower than stock, and chain wrap should be OK.

What do you mean by more options though? Easier to get sprockets to fit, or something else?

yes, also easier to change pitch of chain aswell if you desire. I personally run 520 chain, 17/41, renthal rear sprocket. Well, i think its 41, could have been 42, i cant remember.

Quan-Time wrote:yes, also easier to change pitch of chain aswell if you desire. I personally run 520 chain, 17/41, renthal rear sprocket. Well, i think its 41, could have been 42, i cant remember.

Thanks for clarifying that. I guess if you're having no trouble with 520, I won't worry too much about the strength of the 525 I've ordered.