Tires and Swingarms discussion moved outta pics thread

[buffalobill]

Katanarider, I like your bike, but you need to do the rear wheel swap and get radial rubber on there front and rear.
Not done yet so no good pics yet, but this was me Nov. 1st just taking the panels off to begin my engine swap.

[katanarider]

Katanarider, I like your bike, but you need to do the rear wheel swap and get radial rubber on there front and rear

I don't understand your statement. My wheels are post-98 and they have radial tires mounted. As a matter of fact thats a 170/60-17 rear tire, 1st gen Continental Road Attack to be precise...Loved the long life of that tire...about 8,000 miles !

[buffalobill]

My bad, looked like high sidewalls, reminded me of bias ply.

[katanarider]

My bad, looked like high sidewalls, reminded me of bias ply.

Thats because the tread depth of that Road Attack was about 1 inch deep.
That could be why it lasted so long. In comparison, the Sport Attack I had before I bought the Road Attack had about 1/4 of the tread and lasted about 3,000 miles.

[buffalobill]

Does that 170/60 touch the caliper arm?
I bought a gsxr wheel that's 5.5" wide, and I'm hoping to get a 180/55 in there.
I've measured the space a few times and I'm getting a little over 200mm, but the arm needs to be kinked a bit more to be clear of the tire.
The gsxr wheel came with a 190 on it, and that just barely clears with the arm removed and zero room for adjustment.

[katanarider]

I bent my brake caliper arm as much as possible, well I smashed completely flat with a sledge hammer after heating it with a propane torch. I wish I would have left a little squareness to it so it would maintain some rigidness. During hard braking I believe it flexes ever so slightly, but it hasn't gave out and allowed the brake caliper to move forward/or kink after 5-6 yrs. But to answer your question, if I recall the 170 was about 5mm to that caliper support bar. Its not the best fab work I've done so it probably could have been bent to make just a few more MM of clearance. I do not recall the spacing between the swingarm at all because my bike is lowered and a bigger tire would scrub the undertail/frame. After I broke my hugger I noticed that issue and didn't even investigate it any further.
I have seen a un-lowered post-98 Kat with a 180 tire with out any mods period, on youtube. If your bike wasn't going to be riden hard on the track where your more likely to experience dangerous conditions, I would say try mounting a 180 on your post wheel by denting the swingarm, just for show purposes like slow cruising. If that didn't work out then I would try other alternatives. However, like I said its not the safest thing to do on a track bike and it WILL PINCH on that post wheel. Your best and safest solution would to be contact Kreylyn, hands down. He is the pimp, mac daddy legend when it comes to that mod.

[Kreylyn]

Does that 170/60 touch the caliper arm?
I bought a gsxr wheel that's 5.5" wide, and I'm hoping to get a 180/55 in there.
I've measured the space a few times and I'm getting a little over 200mm, but the arm needs to be kinked a bit more to be clear of the tire.
The gsxr wheel came with a 190 on it, and that just barely clears with the arm removed and zero room for adjustment.

Tire sizes are based upon the width when mounted properly. It's not what the width actually is due to variables, such as rim width.

So that means an over sized tire (190) on a 5.5" rim will be pinched in. So if you measure your going to find that 190 isn't really much if at all any wider than a 180mm tire. For reference, id suggest you do just that and post the results... what is the width of the tire actually mounted on your rim.

With that ... the 180 isn't going to to give you much/any more clearance. You can (and some people have....) put the wheel in and see that it's not touching. The problem is tires flex, swingarms flex, and when riding down the road you will have clearance issues.

Will those issues result in catastrophic fail? Not saying that it's 100%... but I sure as hell would not put myself on a bike setup like that.

Tire manufactures recommend 1/2" clearance either side, absolute minimal of 1/4".

Krey

[buffalobill]

Krey your are the tire cop here.
Looks like I could just get a 170 in there with the 5.5 wheel.
This is for track days, so I wanted a bit more rubber on those lean angles.
Michelin discontinued their 160/60 Power Pilot, and I don't wanna put a 170 on a 4.5 wheel, so I got the 5.5.
The 180/55 would not allow any alignment flexibility.
Thanks.

[katanarider]

I didn't measure the bead, but my 170 Continental Road Attack fit the post98 wheel really well...at least it appeared that way. Although I would not recommend either the Sport Attack or the Road Attack for track days due to lack of grip. For the track you may try the Race Attack as I've not had experience with those yet.
As you may have read by now, not all 170 tires are made to fit the 4.5" wheel.
This can be a issue when you investigate which tires fit that wheel, but I've never seen a tire ad that specifies the bead width... 4 1/2 inches equals 114.3mm just so you know. FYI, I've just gotten my first set of Shinkos not too long ago. I have to give them credit since I'm really happy with the way they handle and the low cost factor. Not one complaint as yet !

[Kreylyn]

For track... I'd recommend you modify the swing arm and brace it. It's not hard to do.

Or... just build one custom from mostly scratch. You could easily take the pivot tube off the stock arm to start with to skip the machining... use flat 2mm sheet steel bent to rectangular matching tube, then create a new arm.

Lots of options.

Krey

[buffalobill]

I have Shinko's on my road bike, 82 GS1100G. I like them and they're real sticky, but on the track, I'll only trust tires that have successful racing programs: Michelin, Bridgestone, Dunlop.

[buffalobill]

For track... I'd recommend you modify the swing arm and brace it. It's not hard to do.

Or... just build one custom from mostly scratch. You could easily take the pivot tube off the stock arm to start with to skip the machining... use flat 2mm sheet steel bent to rectangular matching tube, then create a new arm.

Lots of options.

Krey

That makes sense. After your post, I had a look at my swing arm and illustrations of the GSXR swing arms in the Haynes manual.
They shaped the 600 and 750 Katana swing arms with a taper towards the shaft, the GSXR arms are more squared to the shaft.
It looks like the Katana mufflers need to be moved outward to allow room for widening.

[Kreylyn]

That makes sense. After your post, I had a look at my swing arm and illustrations of the GSXR swing arms in the Haynes manual.
They shaped the 600 and 750 Katana swing arms with a taper towards the shaft, the GSXR arms are more squared to the shaft.
It looks like the Katana mufflers need to be moved outward to allow room for widening.

Possibly on the mufflers. The OEM duels have a tendency to get "pushed" in and give no clearance. It's usually a simple process to "bend" them out a tad. I know ( due to several times on it's side...) I had to pull the passenger pegs out on my bike to make clearance. Being as the mufflers bolt to that... they got pulled out at the same time.

Krey

[katanarider]

Bill, since your building a track bike I think you can get away with chopping the mufflers off behind the secondary hanger. You know just beneath the foot pegs. Then weld on some flashy tips to turn the exhaust away from the bike. Sure its going to be loud like a GP Moto bike, but thats kind of what your doing any how. That would simplify all sorts of stuff so you could go ahead and jet you carbs. Then you'll have plenty of room to show off that beautiful custom swinger. Imagine some cool sponsor stickers displayed on the side of the swingarm as you pass the crowd...lol

[steves]

Actually, depending on the track they may not let him operate it if it's deemed "too loud." I've never seen it personally enforced, but most orgs run rules on noise.