Thoroughly confused about tire sizes and compatibility

[Jiggles]

I'm mostly a commuter so I've decided on some BT45's. Obviously I'm trying to get the best deal on tires but when I look for the stock sizes I can't find them reasonably priced and in stock on most websites. Now I know that different sized tires will fit the rims but I don't know which ones will fit or really even what the numbers mean. XXX/YY-ZZ From what I have read, I've ascertained that the X's document the width, Y's the 'Aspect Ratio' and Z is the tires diameter.

For the front tire, I understand that both a 110/YY and 120/YY will fit. I have no idea what the YY part needs to be though or really how it affects the shape. If I go with a 120 do I still want a 120/70 or something else?

Same for the rear tire, I know certain 130/YY 140/YY and 150/YY will fit but I don't know what YY I would need.

If you could provide your recipe for BT45's and where you got them, that would be very helpful.

And yes, I tried the search function first.

[qwkartist2000]

https://www.denniskirk.com/help_center/tire-sizes.jsp
Posted via Mobile Device

[Jiggles]

Originally Posted by qwkartist2000

https://www.denniskirk.com/help_center/tire-sizes.jsp
Posted via Mobile Device

Ok so a larger YY is a taller tire? Is that the only difference? Will a 110/70 and 110/80 fit the same but the 80 will just be taller?

[qwkartist2000]

I'm not sure because i don't have a bike myself but i figured that would at least explain the numbers.sorry.I'm sure someone one else one here can answer that better than me.
Posted via Mobile Device

[ForceofWill]

I'm assuming it's the same as with cars. The second number should be sidewall size, affecting the profile. Lower the number, lower profile. A 130/70 and 140/70 should be the same overall height, on a 17". The only thing you run into on cars is whether you're going to rub something for going wider. I really don't see the sidewall rubbing anything on these bikes, but that's just from the pictures I've seen.

[Jiggles]

Ok so I found a 110/80V17 and 130/70-17 at cycle gear for a pretty reasonable price. I'm guessing that the 110/80V17 will fit but, what the hell does the "V" mean?????

[ForceofWill]

the 110/80 will be 10mm taller remember. Make sure it fits under the front fender without rubbing. My guess is that the V is a speed rating.

[Jiggles]

Originally Posted by ForceofWill

the 110/80 will be 10mm taller remember. Make sure it fits under the front fender without rubbing. My guess is that the V is a speed rating.

Ugh! Why can't I find a 70 anywhere!!!

["A"]

AFAIK, V is the speed rating for the tire.



L 75 mph 120 km/h Off-Road & Light Truck Tires
M 81 mph 130 km/h
N 87 mph 140km/h Temporary Spare Tires
P 93 mph 150 km/h
Q 99 mph 160 km/h Studless & Studdable Winter Tires
R 106 mph 170 km/h H.D. Light Truck Tires
S 112 mph 180 km/h Family Sedans & Vans
T 118 mph 190 km/h Family Sedans & Vans
U 124 mph 200 km/h
H 130 mph 210 km/h Sport Sedans & Coupes
V 149 mph 240 km/h Sport Sedans, Coupes & Sports Cars
W 168 mph 270 km/h Exotic Sports Cars
Y 186 mph 300 km/h Exotic Sports Cars

[Jiggles]

Originally Posted by aciurczak

The front fender doesn't need to be raised on the 08+'s for just about any tire you'd put on there, even if you go to a wider 120 there's still plenty of space; better tires aren't noticeably taller than the stock 110/70/17's. It was only on the 16" with the '07's and earlier that rubbed the fender with a taller tire like the MT-75's.

Did you get a 150 rear or those 140 BT-090 rear takeoffs that Wes was selling? Some of the 150's do in fact rub the chainguard, but they should just clear the swingarm. The 140's shouldn't change the handling drastically, but you'll give up some quick turnin ability. If the 140's are of a stickier compound than stock what you hope to get in return is a little better traction when heeled over. A 150 on the rear on stock rims with no other changes to the bike may turn out to be a big step backward in how your bike handles.

Thanks @Alex I'm guessing the 110/80V17 will fit then.

[Jiggles]

Originally Posted by N Ja

AFAIK, V is the speed rating for the tire.



L 75 mph 120 km/h Off-Road & Light Truck Tires
M 81 mph 130 km/h
N 87 mph 140km/h Temporary Spare Tires
P 93 mph 150 km/h
Q 99 mph 160 km/h Studless & Studdable Winter Tires
R 106 mph 170 km/h H.D. Light Truck Tires
S 112 mph 180 km/h Family Sedans & Vans
T 118 mph 190 km/h Family Sedans & Vans
U 124 mph 200 km/h
H 130 mph 210 km/h Sport Sedans & Coupes
V 149 mph 240 km/h Sport Sedans, Coupes & Sports Cars
W 168 mph 270 km/h Exotic Sports Cars
Y 186 mph 300 km/h Exotic Sports Cars

So now I can go 149mph!!! SWEET!

[qwkartist2000]

lol
Posted via Mobile Device

[Alex]

Originally Posted by Jiggles

Thanks @Alex I'm guessing the 110/80V17 will fit then.

I'm not sure. A 120/70/17 seems to fit under the front fender without issue (though it raises the front of the bike up enough that it must affect handling a bit). But a 110/80 might be even taller than that. If you can't find a tire you like locally, mail order is only a couple days away.

[Jiggles]

Originally Posted by Alex

I'm not sure. A 120/70/17 seems to fit under the front fender without issue (though it raises the front of the bike up enough that it must affect handling a bit). But a 110/80 might be even taller than that. If you can't find a tire you like locally, mail order is only a couple days away.

I'm having trouble even finding them online -_-

I did happen to find one at motorcycle superstore however it is a 110/70-17 G. Now I believe I read in another thread that it is still the same tire just marked with a G because it was OEM on some bike. So, I'll shoot for it.

Too bad its not V rated, it would have been nice to go 149mph

[Alex]

Link on Amazon
Link on Dennis Kirk
Link on AMT

Here is a link to that OEM G-labelled one. All signs point to it being identical.

[coondog]

Originally Posted by Jiggles

I'm mostly a commuter so I've decided on some BT45's. Obviously I'm trying to get the best deal on tires but when I look for the stock sizes I can't find them reasonably priced and in stock on most websites. Now I know that different sized tires will fit the rims but I don't know which ones will fit or really even what the numbers mean. XXX/YY-ZZ From what I have read, I've ascertained that the X's document the width, Y's the 'Aspect Ratio' and Z is the tires diameter.

For the front tire, I understand that both a 110/YY and 120/YY will fit. I have no idea what the YY part needs to be though or really how it affects the shape. If I go with a 120 do I still want a 120/70 or something else?

Same for the rear tire, I know certain 130/YY 140/YY and 150/YY will fit but I don't know what YY I would need.

If you could provide your recipe for BT45's and where you got them, that would be very helpful.

And yes, I tried the search function first.

With the new gens it's best to stick to design size, 80's are taller and I've seen no mention of them fitting under your fenders. wider tires are stupid is as stupid does. With BT45's V is speed and H is touring, V's are harder to find and 10-15 bucks more per set. You can't go wrong with such a good tire man, either way. 110/70-17 front and 130/70-17 rear. I'd get the V's due to short high speed rides are all I (can) do, but as a commuter depending on distance, maybe H's for you. Happy hunting.

[Jiggles]

Originally Posted by coondog

With the new gens it's best to stick to design size, 80's are taller and I've seen no mention of them fitting under your fenders. wider tires are stupid is as stupid does. With BT45's V is speed and H is touring, V's are harder to find and 10-15 bucks more per set. You can't go wrong with such a good tire man, either way. 110/70-17 front and 130/70-17 rear. I'd get the V's due to short high speed rides are all I (can) do, but as a commuter depending on distance, maybe H's for you. Happy hunting.

I literally cannot find a V that is also a 70 but I have finally found a set that is the same size as the stock tires! Yippee! $192 total

[coondog]

Another great thing about the new gens is your stock size is 1/4" wider than the pre-gens as is. Going extra wide looking for extra traction is money wasted that could be better spent elsewhere on the bike, for performance or farkle. Peace out killer.

[THE BIG SITT]

I got my BT45s from motorcycle-superstore one sale for under $200. A word of advice, call some local shops and quote how much they charge to install the tires. Cheapest place I could find was ~$80 to install. But with that being said, most places discount the install if you buy tires from them. So shop around for the best overall price.

[Jiggles]

Originally Posted by THE BIG SITT

I got my BT45s from motorcycle-superstore one sale for under $200. A word of advice, call some local shops and quote how much they charge to install the tires. Cheapest place I could find was ~$80 to install. But with that being said, most places discount the install if you buy tires from them. So shop around for the best overall price.

I got both tires for under $200, free shipping. I have a local bike mechanic that I go to. He charges $50/hr for labor and will install tires (even on the bike) for $10 a piece

I'm going to get my valve adjustment done and have him install the tires. I may even have him do an oil change since I'm such a lazy ass.

[burningscooter]

wait, what did you end up getting? Specifically, up front.

[Jiggles]

BT45's 110/70-17 G and 130/70-17

Oddly enough the G version was $10 cheaper and the regular version was out of stock

[LoneRonin]

for bt45 go with a stock front (110/70) and a 140/70 rear....I liked that setup alot, although stock sizes are good too.

[THE BIG SITT]

Originally Posted by Jiggles

I got both tires for under $200, free shipping. I have a local bike mechanic that I go to. He charges $50/hr for labor and will install tires (even on the bike) for $10 a piece

I'm going to get my valve adjustment done and have him install the tires. I may even have him do an oil change since I'm such a lazy ass.

See if your guy has any friends in central Indiana… cuz now I feel like I got rapped.

[Jiggles]

Originally Posted by THE BIG SITT

See if your guy has any friends in central Indiana… cuz now I feel like I got rapped.

Lol, well he works out of his garage (illegal) and passes the savings on to his customers