Continental Classic Radials

[Ghostgs1]

Has anyone ever seen or used these? Listed on Ron Ayers online sales, but doesn't show a picture of them. Somewhat expensive,but might be interesting. Continental Conti Classic Attack - Vintage/Classic Bike Radial Tire - Front - 100/90VR19 and Continental Conti Classic Attack - Vintage/Classic Bike Radial Tire - Rear - 120/90VR18

[bwringer]

Very limited sizes available, but looks promising:

http://www.conti-online.com/www/motorcycle_de_en/themes/motorcycletires/conti_classic_en/classic_attack_en.html

They also make the "Classic Racing" (CR) tire:

http://www.conti-online.com/www/motorcycle_de_en/themes/motorcycletires/conti_classic_en/road_attack_en.html

Again, limited sizes as yet. It'll be interesting if they ramp up to other sizes to compete with Avon, Pirelli, Bridgestone, Shinko, etc. who are all making excellent modern tires to fit classic bikes.

[Ghostgs1]

This is the first radial tire I've seen in sizes that will work on old bikes. Hope this trend continues.

[OldVet66]

The sizes are limited but will fit the aluminum rim wire wheels I have in my basement I think. They are labeled dot 177 J 1.85 X 19 and dot 177 J 2.15 X 18. Would the maximum size be 100/90 front and 110.90 rear or could I get away with a 110/90 front and 120/90 rear. I have never tried to step up a size on radials, but it works fine with older types.

[Ghostgs1]

My '79 1000S has the same wheel sizes. For the front I think a 100/90R19 is correct, originally 3.25V19. For the rear 120/90R18 would be correct, originally had 4.00-18 rear tire. Currently running 100/90V19 & 120/90V18 bias ply Dunlop GT501's.

[OldVet66]

I dug a little deeper and the published figures for the ContiClassicAttac is 100/90 R19 57V replaces 3.25-19, 110/90 R18 61V replaces 4.00-18 and 120/90 R18 65V replaces 4.25-18. Stock Suzuki per the shop manual is 3.25-19 and 4.00-18. for the wire wheels. One thing I have learned is if you step up just the rear, the front end feels like it falls into a turn. I just don't know anything about radial motorcycle tires, never had a motorcycle with them on it. I have 110/90 and 130/90 on my cast wheels one size up on each wheel and it handles like a dream. If it's safe to do the same with radials I would like to do the same thing when I put my wire wheels into service.

[Ghostgs1]

I'm sure you would be fine with the slight increase in size. I did the same on on the 1000E that my brother is now riding and it handled very nicely. I have only ridden one bike with radials and it was spectacular, but it also had upside down forks and ohlin rear mono shock suspension also. Not exactly apples to apples.

[tkent02]

I'm curious about how well they would work. On cars, radials are far and away the best way to go, I don't think the difference is as clear on bikes. They don't seem to last much longer than bias ply tires, they provide better traction but maybe that's just because they are using wider tires on wider rims?
Whoever buys these be sure to let us know what you think of them.
It won't be me, at least for a while, just bought new tires for everything.

[OldVet66]

It's going to be a while for me too. My memory is going but someone just told me the other day he switched to wider rims and available radials on his 1100 and the difference is night and day. I've been wanting to use my spoke wheels, and these tire sizes are ideal. Now my next question is what sprocket changes are required going up to an 18" rear wheel. I've got one more Shinko 230 rear tire to wear out after the one on there now before I will be in the market, just want a plan in place for when I am ready.

[bwringer]

I used to have a bike (1990 VX800) that could use either radial or bias-ply tires -- it just happened that the correct tire sizes were available either way.

As stated above, the difference isn't all that pronounced with motorcycle tires.

Radials were generally a bit lighter and seemed more flexible, which are good things. You had a bit more feel, mainly.



Always nice to see the major tire manufacturers paying attention to the olde iron. We already have some incredible options in thoroughly modern tires for our rides, too.

[Nessism]

Bias ply tires have a crisscrossed cord bracing in order to stabilize the sidewall and provide stiffness. Radial tires by definition have no angular bracing between the cord layers (sometimes called a 0* cord angle), in fact, they call them radial because the cord layers literally run from bead to bead in a radial direction (when viewed from the side). Crossed carcass ply layers are the logical design for tall tires such as our GS's use. Radials typically have a very low profile ratio in order to keep the sidewall short, because a tall radial sidewall will have no stiffness. Radials also need wide rims to pull the sidewall tight for the same reason.

I'm curious to learn how Continental designed the sidewall on these tires. There is basically no way to build a true radial motorcycle tire with a tall sidewall, employing a narrow GS type rim, using techniques used on other motorcycle tires because the sidewall would be too flexible. There must be some other sidewall bracing mechanism built into the design.

[bwringer]

It's certainly possible to build radial tires with very stiff sidewalls -- the tires on my V-Strom, for example, are radials (150/70-17 rear. 110/80-19 front). Many of the available dual-sport tires in these sizes are very rigid.

[Stuarth]

Late to the thread as I just bought my 77 GS550 ten weeks ago, but wanted to chime in with some actual experience with the Conti Classic Attack radials. In a word, outstanding! I've been wanting to try these since shortly after I bought my 76 XS650 in December, 2012. I had installed Bridgestone BT45's already though so obviously didn't want to just toss money out the window. Fast forward three years and I put these on my GS, along with Progressive fork springs, Race Tech Emulators, and Progressive Series 12 shocks (all before putting any miles on the GS as the tires on it when purchased were 13 years old). Within 10 miles I had enough confidence in the tires to start pushing pretty hard into turns on my maiden voyage on the GS in the hills heading up to Alice's restaurant here in the SF Bay Area (my favored roads since i started riding in '74). In the 800 miles since, I have been thoroughly impressed with these tires. They act like true radials with no rain groove hunting (unlike the BT45s) and little reaction to road elevation changes that run near parallel to the road. I've been riding many years starting with an RD350 in 74 (how many of you remember K81's?), my then new 77 GS550, and so on. These Contis will go on the XS next. I wish they made sizes to fit my SRX600 too. I am fortunate that my wife is okay with me having multiple bikes- you can see pictures of them in my profile if you're interested, along with some original GS ads that the original owner had saved. There is noticeable wear in the center at 800 miles, but I would expect that as 90% of the miles that I put on my bikes is from commuting to work on the freeway.

[steve murdoch]

Thanks for the report.
While i am more prone to buying tires for their grip instead of longevity, "noticeable wear in the center" after only 800 miles is too much for me.

[Stuarth]

Actually, make that 700 miles. The tire profile is very rounded so I would expect wear to be greater at the beginning (heavy bike, narrow tire, mostly commuting miles straight up and down). I would also expect the wear to slow some as the center flat spot widens and spreads the load, but I don't expect this to be a 5,000 mile tire. I would guess at this point that I'll get maybe 3,000-3,500 miles out of the rear tire which would be about par compared to the BT45 on the XS. Not a low-cost option, but for me the trade off is worth it for those times when I can head into the hills with the GS. Picture of the rear tire as of this morning.

Conti-700 Miles.jpg

Thanks for the report.
While i am more prone to buying tires for their grip instead of longevity, "noticeable wear in the center" after only 800 miles is too much for me.