Topic: got new tires, I didn't screw up, right?

[morpheus991]

So I've had the tires on that came with my bike (cb750 '74 frame, '78 engine) when I got it. Almost no tread left on the rear...time to replace. I did some research  and ended up going with the Dunlop GT501's. Here's the thing, I got a little impatient and ordered them. They come in the right size for the front (100/90-19) but not for the rear (110/90-18) so I got 120/90-18's for the rear, is that bad? Less cornering stability? I know it might be a minor difference but I'd rather be safe than sorry. I want max traction. Thanks, I know tire questions come up all the time.

[mlinder]

120's will be fine.

[76CB5WI]

Yeah your good
you wont corner like you did.
You can go the opposite too and get more cornering with a narrower tire
as well but at a slight sacrifice in touring comfort.

[morpheus991]

#$%*, I wanted good cornering...worse than the 120/80's? Also I just bent my swingarm, that'll be fun to find/fix with my budget...

[BLUE71TURBO]

 The 120 will work great on the rear !  I run a 130 18 on the rear and 110 19 on the front. Corners just fine in the mountains.   

[morpheus991]

great, I hope so. I guess we'll see...once I get a new swingarm.

[andy750]

I used to have the Dunlop GT501s and had a 120 in the rear on my K4  -it corners fine for most of the tires life but it will square off faster than the 110. This will eventually affect your cornering - at least it did for me - became unstable when leaning over - I always thought it was going to slip out. I changed to the 110 (bt45s) and never looked back.

Pic for comparison - 110 v 120s (on bike).





cheers
Andy

[kghost]

Yeah what Andy said....

Before it got square it was brilliant....took 7,000+ miles to get square.

You're all good.

[morpheus991]

I guess 7,000 isn't too bad. The tires I have now are almost completely out of tread on the center and I never feel comfortable cornering so I'm sure it'll be fine. Thanks.

[faux fiddy]

I used to have the Dunlop GT501s and had a 120 in the rear on my K4  -it corners fine for most of the tires life but it will square off faster than the 110. This will eventually affect your cornering - at least it did for me - became unstable when leaning over - I always thought it was going to slip out. I changed to the 110 (bt45s) and never looked back.

Pic for comparison - 110 v 120s (on bike).





cheers
Andy

Stick to the curves, get  suit with a puck on the knee to wear out and avoid straight up. You can find those places out by Hollywood, can't you?

[Raul CB750K1]

For reasons too long to explain here, I have been forced by the spanish DMV to replace my almost-new rear tire, when the same model was good three years ago....

Anyway, the Metzeler Perfect ME77 front was not available with speed index "H", and so this time I've opted for Continentals RB2 and K112. So far so good, at least for somebody who doesn't scrape the kneecap at every turn. I opted for Contis because of the classic thread. In the modern CBSevenFifty I have Michelin Pilot Road.

[BobbyR]

I used to have the Dunlop GT501s and had a 120 in the rear on my K4  -it corners fine for most of the tires life but it will square off faster than the 110. This will eventually affect your cornering - at least it did for me - became unstable when leaning over - I always thought it was going to slip out. I changed to the 110 (bt45s) and never looked back.

Pic for comparison - 110 v 120s (on bike).





cheers
Andy

My experience also, the 120 will square off and when you lean over you will feel the step. I went down a size on my new set. Andy is our long distance explorer. I am sure one of his Ancestors probably beat the Indians here, and went back when he found he could not get a pint here.

[morpheus991]

What size did you end up using and have you seen the results yet? They don't come in the 110/90's and I heard it's important to keep the aspect ratio the same. Returning them isn't really an option because I got them online and it would be a pain to ship them. But maybe I can trade them out at a local shop? I was under the impression that the GT501s are better than the D404s that come in that size? Sh*t, I thought I had it all figured out. Well I still have some more important things to figure out anyway, like fixing my bent swingarm... I'm tired of all this, I just want to ride.

"Stick to the curves, get  suit with a puck on the knee to wear out and aviod straight up. You cn find those places out by Hollywood, can't you?" ...so are you saying ride like I'm drunk?

[BobbyR]

What size did you end up using and have you seen the results yet? They don't come in the 110/90's and I heard it's important to keep the aspect ratio the same. Returning them isn't really an option because I got them online and it would be a pain to ship them. But maybe I can trade them out at a local shop? I was under the impression that the GT501s are better than the D404s that come in that size? Sh*t, I thought I had it all figured out. Well I still have some more important things to figure out anyway, like fixing my bent swingarm... I'm tired of all this, I just want to ride.

"Stick to the curves, get  suit with a puck on the knee to wear out and aviod straight up. You cn find those places out by Hollywood, can't you?" ...so are you saying ride like I'm drunk?

Don't panic. They will be fine for a long time. We are only talking about a few years depending on how much and what type of riding you do. If you are canyon racing it will never show up.

[Alan F.]

Andy is our long distance explorer. I am sure one of his Ancestors probably beat the Indians here, and went back when he found he could not get a pint here.

Heh-heh, he's a hell of a nice guy too.

[andy750]

What size did you end up using and have you seen the results yet? They don't come in the 110/90's and I heard it's important to keep the aspect ratio the same. Returning them isn't really an option because I got them online and it would be a pain to ship them. But maybe I can trade them out at a local shop? I was under the impression that the GT501s are better than the D404s that come in that size? Sh*t, I thought I had it all figured out. Well I still have some more important things to figure out anyway, like fixing my bent swingarm... I'm tired of all this, I just want to ride.

"Stick to the curves, get  suit with a puck on the knee to wear out and aviod straight up. You cn find those places out by Hollywood, can't you?" ...so are you saying ride like I'm drunk?

Don't panic. They will be fine for a long time. We are only talking about a few years depending on how much and what type of riding you do. If you are canyon racing it will never show up.

I agree with Bobby. The tires are very usable and are sticky enough in the corners for most of their life. When it gets to the point and you lean over and feel a "step" then you know its time to change them. Dont worry about it now - go out and ride them! 7000+ miles is something to aim for.

have fun
Andy

[Retro Rocket]

If you want longer life and longer time until it squares off, look at dual compound tyres, there are some good ones out there and they have a harder compound in the middle to slow down the squaring off.

Mick

[HondaMan]

#$%*, I wanted good cornering...worse than the 120/80's? Also I just bent my swingarm, that'll be fun to find/fix with my budget...

Bent a 750 swingarm. 
Can you show a picture? That's hard to do. Contrary to popular (mis)conception, these are one of the strongest swingarms to hit the street, short of the modern cast monoshock sportbike types.

[morpheus991]

I'll try to get a picture up tomorrow sometime. I think it happened when I hit one of the million creator sized potholes I go over everyday in Los Angeles. Normally if I'm going to hit one I raise up of the seat but recently I thought to myself, "Hey, I have shocks, that's what they're made for!", wrong.