4.5" vs 5.5" rear wheel handling

[sfdownhill]

I've flattened my arse while searching here [and there and etc etc] and reading up on Hawks the past few days - such a wealth of information here. It took me a couple years on the VFR forums to get 'up to speed' where I had something to offer, and was well worth it.

Topic: the handling of two popular sizes of rear wheel conversions. Many threads, many concepts, but even among the Hawk racer community, I couldn't find clear assessment of the handling difference between a stock size 17* x 4.5" and an alternative 17* x 5.5", such as the **VFR 5 and 8 spoke wheels, with the 17 x 5" 94-97 **VFR as a third width option.
[*17" is only mentioned because OEM RC30 and NC30 wheels are 18" diameter and that's not being considered]
[**Recognizing that spindle mods will be needed for rear wheel conversions]

Here's the question: What is the difference in a Hawk's handling [Given that suspension is properly sprung, valved, and set up, good brakes, etc] when using a 4.5" wide wheel and 160 width tire vs the same Hawk with a 5.5" wheel and the same make/model tire in a 180 width?

[Talon]

Having ridden both on track I much prefer the 160 section tire on a 4.5" rim. The bike is much more responsive with the 160. I have also run a 165 (which is really ideal on a 5" rear) on a 4.5". While not bad, I still prefer the 160, especially on tighter, more technical tracks.

[sfdownhill]

Thanks Talon - that makes sense. Nice to hear a real world comparison.

[6]

Having ridden both on track I much prefer the 160 section tire on a 4.5" rim. The bike is much more responsive with the 160. I have also run a 165 (which is really ideal on a 5" rear) on a 4.5". While not bad, I still prefer the 160, especially on tighter, more technical tracks.

I agree completely about the 165 on a 5" rim, fits likes glove, far better than on the 4.5.

I've raced on the 4.5, 5, and 5.5 and absolutely think the 5 and 165 is the combo.

BUT sfdownhill to answer your question, there is no clear answer because there is no clear answer. Ask 10 different hawk racers that question and you are bound to get a handful of different answers. Some riders perfer different things. Everyone rides a little differently and "feel" is a very subjective subject with a lot of variables.


But as a general answer, the thinner the tire the quicker the handling. Wider the tire the slower. But some bikes can make use of all that tire better than others and it becomes worth it.

On the street it matters far far less.

[ricksax]

I'm running a 170 Dunlop Roadsmart III on a VFR rear wheel. No racing, just curvy roads with some very slow switchbacks. More tire than I really "need," but I like it very much.

[tian647]

Thought I was accidentally on ducati.ms again with this thread. FWIW, on a carby SS the skinny wheel felt nicer to me in the twisty bits. No experience on a Hawk but with low power/light weight I don't expect a wider tire would improve much here either.

[sfdownhill]

Thanks guys, good cross section of comments. So many subjective questions are like this one. I like the phrase “Ask ten different Hawk riders, get ten different answers”. Thanks

[Hordpower]

Is this a race or street question? If racing, it's really more a question of being able to get a good tire for a 4.5" rim. Slim to none. I raced almost exclusively on 165 slicks fitted to a 5.0 or 5.5 wheel. Just about perfect IMO, but the selection of tires that size is now thin with the disappearance of 250GP bikes. For street use I don't think there's a huge difference. Really it's about finding a tire that is made to fit whatever wheel width you have. If that's a 180, then find the smallest 180 you can.

[6]

Is this a race or street question? If racing, it's really more a question of being able to get a good tire for a 4.5" rim. Slim to none. I raced almost exclusively on 165 slicks fitted to a 5.0 or 5.5 wheel. Just about perfect IMO, but the selection of tires that size is now thin with the disappearance of 250GP bikes. For street use I don't think there's a huge difference. Really it's about finding a tire that is made to fit whatever wheel width you have. If that's a 180, then find the smallest 180 you can.

No more 165 tires?

I'm old now.

[Talon]

No more 165 tires?

I'm old now.

Dunlop still has the KR451 165/55 in a couple different compounds. Other than that...nada.

[JanM]

You could look at SuperMoto tires, eg. Metzeler. We used the Michelin SuperMoto tires to good effect on 3.5"x17" and 5.5"x17" rims before the racehawk was retired. Other than that, availability rules, so check locally. Modern supersport tires with thread pattern are very good.

[sfdownhill]

Thanks for all the replies.

“Is this a race or a street question?”
For the Hawk, it’s a street question. Once I get it running well, I may take the Hawk to the track to refine setup, but even then I’d be on good super sport DOT tires, Dunlop Q3+, Michelin Power 5 or similar.

”Dunlop still has the KR451 165/55 in a couple different compounds.”
Love the KR451/448, have used them on the track bike for going on 3 years now.

”You could look at SuperMoto tires, eg. Metzeler.”
Supermoto rubber is a great idea - hadn’t thought of that, but will check them out.

[Ahrma32]

I am racing my hawk on stock wheels. Bridgestone Battlax slick rear. 165./630

stickboyracing.com tire guy extrodanare

[Ahrma32]

[sfdownhill]

Nice hoops Ahrma32 - thanks for the feedback.