Mixing tyres?

[kiwi cowboy]

gsxr400 in pre89 class.
question;-whot would the pro,s [if any] be of putting a slick on the front and leaving the road tyre on the back. the reason i ask is i cant buy a 130-70-17 rear slick but there are plenty of 2nd hand 120-70-17 front slicks.presently running sport demons having fun

[avgas]

run the 120 - it will help you corner a bit more on the track, just be careful when you open on the straights.
running road tyre is ok - but it will be gone pretty quick.

[YellowDog]

When you are cornering at speed you need to have both tyres handling with the same performance characteristics. The road tyre will have way too much friction. I know it is on the back and all that, but it will affect the balance.

IMHO - Mixing tyres is best avoided.

[malcy25]

When you are cornering at speed you need to have both tyres handling with the same performance characteristics. The road tyre will have way too much friction. I know it is on the back and all that, but it will affect the balance.

IMHO - Mixing tyres is best avoided.

Can you expand on what you mean by "friction" as grip could be construed as "friction"!

Kiwi Cowboy. I don't know you as I'm a long way away, but what have you got now and what's the problem? Slicks are not necessarily the answer to all grip evils. Are you sliding regularly now? How wide the are the rims you are using? It could be that something like the GPR A10 dunlop may provide a very good alternative and that a 140 may fit and be available to match say a 110- front

Over the years I've seen many guys with a slick on the rear and a "road" tyre on the frotn due to handling problems they are trying to over come - ie the front slick contruction has provided an issue.

[Chrislost]

When you are cornering at speed you need to have both tyres handling with the same performance characteristics. The road tyre will have way too much friction. I know it is on the back and all that, but it will affect the balance.

IMHO - Mixing tyres is best avoided.

I personally thought that friction was what tyres did.

The more friction, the more grip...

Run whatever, once you have a few races under your belt then start to change stuff. I ran one set of road tyres for the whole of the winter series last year on my vfr, exept when it rained and i used wets, so lasting shouldnt be much of a problem unless you like to burnout after every race. Had some pretty sweet battles with the posties bikes that were running everything from shinkos to slicks.

[Chrislost]

How wide the are the rims you are using? It could be that something like the GPR A10 dunlop may provide a very good alternative and that a 140 may fit and be available to match say a 110- front

What he said. GPRa10s

[t3mp0r4ry nzr]

pros of running a slick front and leaving roadie on the back?
cost (if 2nd hand) and longevity spring to mind of the front tyre.
Cons?
slick takes longer to warm up so you would want to be running warmers and ride hard to be getting the slick into the right temp zone to be working.

You racing over winter? if so, how fast can you get the temp up?

Im running road tyres this winter, b/c they should be more suited to the low track and ambient temp's and low power demands of a 400. Well thats my theory, will see how that pans out in a couple of weeks

[GSVR]

gsxr400 in pre89 class.
question;-whot would the pro,s [if any] be of putting a slick on the front and leaving the road tyre on the back. the reason i ask is i cant buy a 130-70-17 rear slick but there are plenty of 2nd hand 120-70-17 front slicks.presently running sport demons having fun

I looked up the standard fitment for a GSXR400 and its listed as a 140 rear and a 110 front.

If I was running over winter and didn't have a set of wets I'd run something with a little tread at least. Pretty sure Dunlop make a good 150 rear. Take a look at what others are running as I reacon you might even get away with a 160 (if it clears the chain) which is pretty much the normal size for an F3 bike.

What years your bike?. How wide is the rear rim? There should be heaps of good tyres out there that will fit your bike.

http://www.gsx-r.eu/History_gsxr400.htm

[scracha]

Pretty sure Dunlop make a good 150 rear. Take a look at what others are running as I reacon you might even get away with a 160 (if it clears the chain) which is pretty much the normal size for an F3 bike.
http://www.gsx-r.eu/History_gsxr400.htm

Have only ever tried GPR's as they seem to work well and get em for a very good price. All these sizes are available. Tried a 160/18 on the CBR400 but it slows steering down to much and the 150/18 works a lot better. The 600 'cane' runs a skinny 140/17 (stock it's 130) on its arse end so that size is available. Unless you're riding off the edge of the tyres then I wouldn't stress. I'm in agreement with ChrisLost...on a stock 400 you'll be able to do the whole winter series on one set of tyres (and a few more meetings :-) ) as the weight and power output is so modest. It's the heat cycles that fark em up more than anything.

Anyone running slicks without warmers is bonkers IMHO. The road tyres are a lot more forgiving in regards to temperature and tyre pressures.

[kiwi cowboy]

Can you expand on what you mean by "friction" as grip could be construed as "friction"!

Kiwi Cowboy. I don't know you as I'm a long way away, but what have you got now and what's the problem? Slicks are not necessarily the answer to all grip evils. Are you sliding regularly now? How wide the are the rims you are using? It could be that something like the GPR A10 dunlop may provide a very good alternative and that a 140 may fit and be available to match say a 110- front


Over the years I've seen many guys with a slick on the rear and a "road" tyre on the frotn due to handling problems they are trying to over come - ie the front slick contruction has provided an issue.

thanks for that.
the sticker says it should have 110-80-17 on the front [its got a 110-70-17]on it. Rear should be 140-80-17 [has a 130-70-17on it]its not sliding on a dry track but was a bit niggly in the front at terotonga in the first round in the wet.

[kiwi cowboy]

Have only ever tried GPR's as they seem to work well and get em for a very good price. All these sizes are available. Tried a 160/18 on the CBR400 but it slows steering down to much and the 150/18 works a lot better. The 600 'cane' runs a skinny 140/17 (stock it's 130) on its arse end so that size is available. Unless you're riding off the edge of the tyres then I wouldn't stress. I'm in agreement with ChrisLost...on a stock 400 you'll be able to do the whole winter series on one set of tyres (and a few more meetings :-) ) as the weight and power output is so modest. It's the heat cycles that fark em up more than anything.

Anyone running slicks without warmers is bonkers IMHO. The road tyres are a lot more forgiving in regards to temperature and tyre pressures.

SHIT i was led to belive that slicks heated quicker than road ies.
funning sport deamons at thr mo and they are doin the job ok but might check these gpr's out cheers

[GaZBur]

thanks for that.
the sticker says it should have 110-80-17 on the front [its got a 110-70-17]on it. Rear should be 140-80-17 [has a 130-70-17on it]its not sliding on a dry track but was a bit niggly in the front at terotonga in the first round in the wet.

I was using GPRa10's at Teretonga. I have been told by those that should know that slicks will not heat up enough by themselves over winter at Teretonga when temp below 10 degrees. My GPRa's slid around heaps until the 2nd lap and by then the guys with tyre warmers and wets were miles ahead anyway. At least the Dunlops will slide around a bit before just dumping you on your arse.
Have a good rnd 3 - see you on the 12th July.

[budda]

Gpra10's are a good compromise, but you'd be well advised to try either BT090's ( equiv to GPRA10's - made for mid-size race bikes ) OR wait a few weeks for the all new BT003RS; the very latest development, made for the job and in the right sizes too

Go and see Graham or Paul, tell them a portly chap of a Ginga persuasion sent you !!!!!!!!!!!! And ask him for some Goldfren pads too !!!!!!

[DEATH_INC.]

I've run a 208GP dunlop (treaded race tyre, like in wss) front with a D220 (sport touring) rear around taupo a while back....it wasn't too bad.

SHIT i was led to belive that slicks heated quicker than road ies.

lol, you're in for a surprise then, they take around a lap to ride on even normally, then another to get to a raceable temp, even on a semi warm track....