GSXR750 SRAD needs some TLC

[Madmax1993]

Stick with a 180 on the back. You don't really need a 190 on a 750 of that era. More options, cheaper, and turn in quicker.

Ah, good to know as it's had a 190 on there from before my time. I think I'll have more choice of tyres by going to 180. What about the front, could that go the other way and put a slightly wider tyre on, as I've sometimes thought it looks a bit noodly with the 120 on there?

 

[Madmax1993]

This is the bike in case anyone wonders why anyone would be so heathen as to ask about ADV style tyres on a sports bike.

 

[Markybeau]

I don't understand what you're trying to achieve by putting ADV type tyres on it. If you're looking to ride offroad on it then the tyres will need to be narrower because of the fork and swingarm clearances.

A wider front will likely not fit as the clearance with the mudguard is tight anyway. It will also slow the steering, making it feel less willing to turn. Wider than 120 is not a common size in a 17" tyre.

If you're not very experienced with motorbikes I wouldn't advise going there. ADV tyres don't provide the same level of grip as road tyres.

 

[Madmax1993]

Aesthetic reasons mostly.

I was hoping something like this might work. I'm not riding the bike on track days etc, it's more an occasional leisure pastime these days.
I guess I didn't really think through the implications of a (slightly) wider tyre on the front. I think the pirellis pictured come in the stock 120/70r17 at any rate, so might see if that's achievable on the shoe-string budget I've laid out for the project.

 

[Markybeau]

Shoe-string budget + motorcycle tyres = quietly closing door and walking away from conversation.

 

[novocaine]

Shoe-string budget + motorcycle tyres = quietly closing door and walking away from conversation.

guess it depends how thin the shoe string is. last years tyres can be had cheaper than this years, but still not shoe string.

steer clear of ADV tyres, road bike tyres are just nicer and riding on the road (where this bike belongs) will be a much more pleasant experience (less tyre noise, more grip, less tyre wobble, etc. etc. etc.)

 

[Madmax1993]

Lads, come on... I said shoe-string budget for the project as a whole. Of course I understand the economics of quality tyres and will spend appropriately, even if it means delaying the project a little.
Also, there's a difference between what my SRAD was built for 25 years ago and how it will be used nowadays. It's not a track weapon at the bleeding edge of technology any more, it'll see a bit of gentle cruising.

 

[novocaine]

Lads, come on... I said shoe-string budget for the project as a whole. Of course I understand the economics of quality tyres and will spend appropriately, even if it means delaying the project a little.
Also, there's a difference between what my SRAD was built for 25 years ago and how it will be used nowadays. It's not a track weapon at the bleeding edge of technology any more, it'll see a bit of gentle cruising.

still stick with road tyres.

 

[Markybeau]

Then I would put a pair of Michelin Pilot Road 2 or 3 (or similar) on which will be all the tyre you'll ever need, will be confidence inspiring, and cheap, as they are an older product. Then spend the rest of your budget elsewhere.

ADV = Wider tread pattern = smaller contact patch = less grip = less effective braking capability on an old bike with old brakes. No mention of track riding was implied in the making of this, or any other, statement .

 

[denco.h1e]

Hi,

Motorcycle tyres has been my job for 35 years and I hope you don't mind if I give you a few facts. You don't have to follow them, it's your bike after all , but please read and understand the results of what you're hoping to do.

For most regular street bikes, over the years the front tyre size has narrowed down to one size: 120/70-17. On a 3.5" rim (your size) it offers the best balance of performance and comfort on the road.

35 years ago a couple of manufacturers experimented with 130/60-17 front size but it gave no advantages and a few disadvantages and was dropped within a handful of years.

Rear tyre size has changed a bit over the years with sizes growing from 180/55-17 at the end of the '80s, to 190/50-17 to 190/55-17 to today's 200/55-17. But the size fitted to a bike is dependent on the rear wheel width.

Your SRAD has a 6.00" wheel and in its day the 190/50-17 was the optimum tyre size for this rim width.

It is permissible to fit a 180/55-17 tyre on a 6.00" rim but the tyre's profile will be flattened. This is to be expected as the 180/55-17 was designed for a 5.5" rim. By fitting it on a 6.00" rim you are pulling the beads farther apart than is optimum and the result is a flattened profile.

In day-to-day riding you might not notice any effect But in sporty riding you will be riding very close to the narrower tyre's tread edge and at bigger lean angles your contact patch will be reduced as you ride off the edge, which I'm sure you'll agree is not desirable.

Even with an optimum sized tyre for any given rim width, under hard cornering you are starting to ride off the tread's edge, but fitting a narrower than optimal size for the rim only exacerbates this.

My advice would always be not to fit a 180/55-17 on an SRAD, stick with the correct 190/50-17 size.

Unfortunately this would eliminate fitting ADV tyres on your bike. Even though many tyre manufacturers approve the fitting of ADV tyre on sports and naked bikes, none of them make ADV tyres in 190/50-17 because no ADV bikes use this size.

It's a shame that Suzuki chose to fit a 6.00" rim of the SRAD because every other GSX-R750 from '92-'95 and '00 until it was dropped a couple of years ago the bikes were fitted with 5.5" rims and 180/55-17 tyres, which would give you any number of ADV tyres to choose from.

if it was my bike I'd choose an entry level street tyre in 120/70-17 and 190/50-17 from one of the main manufacturers, any of which will give more than enough performance for your stated riding style.

For my money, in the entry level sports tyre category Bridgestone's S21 is by far and away the best tyre.

But if you're looking for a more sport-touring, all-round tyre there are several really good entry level tyres. In alphabetical order: Bridgestone BT-023, Metzeler Roadtec Z8, Michelin Pilot Road 4 and Pirelli Angel GT being the standouts.

It's worth pointing out that any of these entry price level tyres will have way more performance than even the best tyres from when the SRAD was launched in 1996.

I hope all of that clears things up rather than complicating matters, but let me know if you have any more questions.