Yamaha TRX850 Enthusiasts Forum

An acquaintance of me has some track used tyres and offered a 180 rear tyre for the TRX (the Pirelli Corsa).

All I have heard is that this is not possible with the original swingarm and rim?

So I just told him that with the 5 inch rim 180 is to wide. He promptly told me that, sure - its not optimal but you can mount a 180 tyre on the 5 inch rim.

The price is really good so I wonder if anyone actually has done this to their TRX and if so, with what result?

Cheers.

Of course you CAN do it but you`ll compromise how the tyre works. The tyres sidewalls will be pulled into the slimmer rim, this will allow the tyre`s treaded area to move around more while cornering as the sidewall is no longer in it`s optimum angle to the rim for support and rigidity.
I WOULDN`T do it myself.
Plus, you may find the tyre will foul the swingarm or hugger (if one`s fitted).

Hi strix!

I agree so far with Mincehead - but from my experiences the 180 tire will not touch the original swingarm; it even doesn't when fitted on a 5,5" rim which I use for riding on the race track.

If the price is as good as you say you can try it - but beware: tires for track use are often only good when heated with tire warmers before riding!

You can as well bring them to the right temperature with riding but be very careful on the first 2 - 3 rounds!

Other than on a race track it is not recommendable to use such tires because usually they don't reach their minimal operation temperature with riding on the street.
And then a cheap tire suddenly becomes very expensive!

Beside this I found that the only difference between a street legal 170/60 Michelin Pilot Power and a 180/55 Michelin Power One for race track only is that you have to lean more in the corners (oh and that with high air / tarmac temperature in summer the Power One should have more reserve; but so far the Pilot Power worked perfectly also on two consecutive track days with 36°C!)

But as said: You most probably won't have any advantages from it but under the right conditions you can try a 180 rear tire on the standard rim.

Rubberized greetings from Munich!

Thanks guys. I now have the info I need.

Actually it isnt a slick or cut slick its a street tyre on the high performance end of the scale. Pirelli Corsa III. Have got some good reviews but I was sceptical if it could fit with the original swingarm.

So Holger and Mince - thx for info I will have to ponder on this. I might try since the Pirelli tyre has really stiff sidewalls.

The price is veeery low so worth trying I think.

Will get back if I did and with what result.

Cheers.

Rubberized greetings? Makes me thinking of certain clubs where men in rubber clothing takes an eye to eachother

So, I decided to try it out!

The essential: It works great and the clearance is good with no fouling of the swingarm etc. Turn in is as good as before (!!) and I feel more confident with that extra "planted" feeling the new 180 tyre gives me.
I went with a set of Pirelli Supercorsa (dirt cheap) both front and back. For me it also included going from 120/60 to 120/70 - great upgrade!

Im sure it has a lot to do with what tyre you fit but I have to say that there seems to be no drawbacks with fitting a 180 tyre to the 5 inch original rim. The tyre gets a very nice and rounded shape - better than with my old 160 tyre =)

If I can get something like 4000 miles from this setup I will be more than happy (mostly road, occasional track).

I go against what seem to be the most common opinion here about 180 rear tyre on std rim and say that it works really well!

Two pics. No 1 to show clearance and no 2 just to show that it is a 180/55 tyre.

I've run a lot of different tyres on my TRX over the years and one thing i've found is that you can't trust the manufacturers to be truthful when it comes to tyre width. I've run verniers over the dunlop 150's i was using and they were actually 155's . Bridgestone 160's were 157's. Avon 170's are 165's. The list goes on and on. The Pirelli's may actually be 175's. Another 180 tyre may actually be larger and could possibly foul the swingarm. just something to watch out for i suppose.

I believe that you are right. The tyre guy said that the Pirelli Supercorsa is quite narrow - hence why it might fit so good on the 5" rim?

Im happy anyway and will try the more road oriented tyre next go. So far so good and the Pirellis seem good on standard rim.

The biggest i found was a dunlop D208 160 which measured 178mm.
Dave

Result.

Tons of grip and confidence. Somewhat slow in turn-in but that was remedied with lowering the front a couple of extra mm. Next season I will raise the rear instead, since the bike is a little bit to low right now (has to really tuck in my toes).

A mix of mostly road and some trackdays. Tyres are almost done but I got about 4.200 miles from them and that from an unbeatable price. SP1 front (still useable) and SP2 rear (done).

So the conclusion is that 180 is working with standard rim, at least the Supercorsa 180/55 that is a bit narrow apparently.

Just sharing for those of you who wants to try.

Strix wrote:Result.

Tons of grip and confidence. Somewhat slow in turn-in but that was remedied with lowering the front a couple of extra mm. Next season I will raise the rear instead, since the bike is a little bit to low right now (has to really tuck in my toes).

A mix of mostly road and some trackdays. Tyres are almost done but I got about 4.200 miles from them and that from an unbeatable price. SP1 front (still useable) and SP2 rear (done).

So the conclusion is that 180 is working with standard rim, at least the Supercorsa 180/55 that is a bit narrow apparently.

Just sharing for those of you who wants to try.

I have bin thinking of trying a 180 55 on the back as I have a set of metzler race tecs in my shed left from my old race bike, arftere reading this going to give them a go! I have also herd that all the tyres that are more track tyres are narrow!
Thanks this hase helped me alot

Looking at rear tyres also at the mo and there's a few super corsas on Ebay that have done a few laps but look like they have quite some life left in them. Prices are reasonable but they are 180/60 insead of the usual 180/55... is it an issue to fit on a 5.5inch rear rim?

drix wrote:Looking at rear tyres also at the mo and there's a few super corsas on Ebay that have done a few laps but look like they have quite some life left in them. Prices are reasonable but they are 180/60 insead of the usual 180/55... is it an issue to fit on a 5.5inch rear rim?

I no that the tyres you are on about on ebay are relly 189/60 as have a friend that has got a set on his yzf750, if you have a yzf750 rim (5.5) then you will be fine, but if you have a trx back wheel (5) then I no the tyre will be to big, so better off with a 180/55 hope that helps