Topic: Avon tires today

[HondaMan]

I've bought 2 new Avon Road Rider tires in the past 6 months, and they both exhibit the same issue: out-of-round.

The last one that I bought in June (110-90/18 rear tire for the 550 in my last book) is perfectly mounted per the alignment ridges on the sides, but the area about 10" long nearest the AVON logo on the left side of the tire is about 2mm 'taller' in the middle of that section than the rest of the tire. Riding it makes the bike 'pogo' at the back, especially around 35 MPH. This is quite a lot of out-of-roundness!

The other one is a 100-90/19 that I just put on the front of my 750 when I replaced the front rim (last month) it's been hanging around the garage since last January or so (2024) as I'd wanted to change out the old 3.50-90/19 from about 9 years ago, and make it metric like the rear tire. It has a similarly raised section on the tread, also right near the "AVON" on the side of the tire. So, I'd estimate this to be some sort of mold-shape problem at Avon? Dunno...

I worked a lot with Gates Rubber here in Denver when their headquarters were here: they made the molds for new tires and upcoming development tires here back then. I has lucky to learn quite a few things about how the various tires are made: many motorcycle tires are molded in one shot over their cores, while some are 'layered' in strips over their cores and are harder to make perfectly round then. This makes me wonder how Avon is making these?

All the Avons I bought and used in the previous 2 years (2022-2023) are/were fine, and were round and smooth leaving here. These 2, not so much...

[69cb750]

Balance ?

[Kelly E]

We have Avon tires on over half of our bikes with no issues. Since we bought the last ones Avon was bought by Cooper Tire. I have had issues with Cooper tires before including recently. 

[Flyin900]

I've been using the Avon Roadrider MK11's on a good number of my bikes over the last 5 years with no issues. I really like the tire. That said the last set I bought was for my 1983 CB1100F and was 2 years ago. I know the outfit was sold around that time. Seems it was Cooper Tire as the new owner per the other poster.
Maybe a change of the process or equipment that was used by the original Avon Company vs the Cooper Tire process. You may have just got a bad batch too, if they are out of round as indicated. I have only had one tire years ago that was defective from new and the seller replaced it no issues. It wasn't an Avon tire back then with the issue, it was another brand.

[HondaMan]

It's hard to imagine these 2 tires are a 'bad batch' situation, given they were bought over year apart and from 2 different distributors, and are 2 diameters.
I just hope they get "it" fixed, as they are have been my favorite tire for decades, for these older bikes, after all tires went metric. They've always been stellar, and with rubber that outlasted anything else I tried by multiples, like 5x to 8x longer than, say, Bridgestones, Continentals, or Pirellis.

Maybe they will improve once they do get it moved to France, if Cooper Tire is going to follow through on that plan.
Better yet, maybe Cooper will bring them to the States? That would be cool. 

[HondaMan]

I've been using the Avon Roadrider MK11's on a good number of my bikes over the last 5 years with no issues. I really like the tire. That said the last set I bought was for my 1983 CB1100F and was 2 years ago. I know the outfit was sold around that time. Seems it was Cooper Tire as the new owner per the other poster.
Maybe a change of the process or equipment that was used by the original Avon Company vs the Cooper Tire process. You may have just got a bad batch too, if they are out of round as indicated. I have only had one tire years ago that was defective from new and the seller replaced it no issues. It wasn't an Avon tire back then with the issue, it was another brand.

Hey, Flyin': do you have some cool pix of your 350F bikes to inspire me? I just started rebuilding mine - which looks like it was stored out in the open for 20 years before I got it 10 years ago.  It's pretty bad.

[kyle750]

I just finished installing new wheels, spokes, and Dunlop K70s on the front and back of my CB750. Wheels trued and balanced and new NOS Honda brake shoes installed. I've never seen the Avon tires.  Just curious how is the ride and handling different between the Avons when compared to the Dunlops??

[HondaMan]

For many years, now, the Avons have been (IMHO) head and shoulders above the others when touring high-speed Interstates (USA), curving mountain roads and commuting to work, and in any weather (short of iced pavement!) on my 750. I have tried some 10 other brands in those years (all on the same bike), but only found the Avons to wear like they were iron while also gripping pavement close to roadrace tire stiction levels, and good to triple-digit speeds while carrying (sometimes seriously overweight) significant loads: I never toured "light" since 1980 but for 1 trip to Texas in all that time (over 80,000 miles of actual use). Before them I had tried some 6 Orient-made brands and 3 Euro brands (still common today) and while the Euro ones generally handled and gripped pavement better than the Orient's versions (even the Euro Dunlop vs. the Japanese versions of it), the Avons gave easily twice the mileage with no handling quirks I could ever discover under any riding conditions I encountered. That's why I've so often recommend the Avons, and why I'm pretty torqued over this 'bug' in their recent production. I can spend the same $$ elsewhere and get good performance, etc., but in terms of how LONG I'll be riding them, they won't even come close.

[PeWe]

Mark, I have also got a tire out of run.
Michelin  Road Classic 130/80-18.
I'm sure that can happen with all tires.

A bump of 2.5mm on a 1/3 of its circumference. I could not make it better despite several attempts, lots of tire assembly lube.

I was lucky to get a new tire about one year after purchase. The previous  tire lasted much longer than  I thought.

I had also ordered new tires recently from same seller so I had one extra to use.
No problem with that, glided  on and found a perfect fit after it was pumped with 4 BAR, reduced to 2.8 BAR

I got a shipping pickup of the bad tire plus a new tire in return, same model.
That tire glided correctly on direct when time to mount it. No run out at all.

I do not want to order tire too early today due to the risk of getting a bad one. All tire sellers might not be that kind to accept a complaint one year later.

My rear tire that is closest to be replaced will last a good part of next season too, almost 4000km left. (5028km done)

I had another tire that must have been out of round on my K2. Did the wheels over a year before the complete build of the bike.
Always bumpy front. Not much but bad enough. Heidenau K40 3.25-19

The bike got the front wheel of the K6 when it got wider alu rims. Much better. The tire had done more than half of its life .

My learnings:
Good idea to measure before mounting a bad setup on the bike.

Rim first to verify the small run out.
Measure again on tire. Just find the flat area. The Michelin has a narrow area in the middle.

So I have to wait to order a new rear  tire. I found a seller with good price of the Michelin rear my K6 need late next season.
It depends on how much I'll use my K2 also using Michelin Road Classic.

The K2 had earlier a bad Metzeler ME77 4.0-18. It had no run out, but the thread had.
Thread was worn out on 1/3 of the tire when it had 2.5mm left on  the other side. It had not as good grip as other tires from the very beginning. A really bad tire.
I'm sure really cheap chinese tires are better.

Below before checking the tires to my K2, borh front and rear. (An eventual run out is visible when rotating rhe wheel.)
Tires were good


Front rim and rear wheel with tire.

[HondaMan]

Per: I might try one of those Michelin Road Classics like you show above: they look to have have a similar tread to the Avon, which I've grown accustomed to over the years. It is most excellent in the wet and doesn't wiggle around under me on dirt roads, either. While my favorite tread pattern is those with a circumferential center groove (improves Interstate stability when riding 1-handed), almost all the tires I have seen with that groove are also tires I would not wish to use for [other] quality issues - like poor carcass layers or too-slippery rubber.

Now, to see if my local tire seller carries Mich...

[PeWe]

The Michelin lasts long as well.

[M 750K6]

My 750 had nearly unused Bridgestones when I bought it. I suffered vibration at the front. On a ride I lent over to watch the wheel and it was all over the place. I checked the rim, it was fine. The tyre wasn't round, it kicked out over a 3" section. I dropped the air from the tube, reseated it and no joy. The tyre was wider at this one point. No sign of scuffing or impact, it was simply not moulded correctly. Gave up, bought Avons and fixed it.

The UK Avon factory closed last year. I think production moved to France. I'm not far off replacing my rear again. In light of your experience I will source a replacement from my local bike shop and warn them, plus check it before letting them fit it. Thanks for alerting us.

This is a great excuse for outsourcing my least favourite maintenance job 

[Stev-o]

I have Avons on my Z1, wanted the best tire for that bike and it never disappointed.  I may be due for a new one, not happy to hear about any possible issues.

[Flyin900]

Mark,

Here are some pictures of the 1972 CB350F build. I did a large previous file and it was lost when I tried to upload it, so I will try with a smaller bunch or pictures in each post. I have sold off most of my bikes now being in my mid 70's, so only 3 bikes are left in the stable. The CB350F went with a bunch of other bikes earlier this year to a Quebec collector near Montreal.

I stripped the frame and repainted it and replaced the Chinese rims with proper DID ones. I had the rotor Blanchard ground at TruDisc in Michigan. All control switches were replaced with correct OEM Honda parts.

[Flyin900]

Another batch of pictures.

The disc rotor was refinished as previously noted by TruDisc.

[Flyin900]

And another batch

[Flyin900]

One more 

I repainted the Candy Bacchus Olive finish the bike came with and used a custom mix with more emerald green in that mix. The seat was a DSS reproduction and no HONDA logo present. I used a correct style stencil and added the logo to the seat panel. Every bolt and JIS screw was replaced with new on the motor and frame.
The exhaust headers and the tail section of the mufflers were sprayed with Eastview's internal ceramic coating as shown on the headers. It reasoned the original pipes where pretty thin metal and this would offer some internal protection from rust. Plus it concentrates and focusses the heat away from the outer chrome finish.

[Flyin900]

Last batch. Aren't you glad you asked. 

Here is the bike in the finished stage where it shared a section of my family room. Along with my 1966 CL77 Scrambler and the 1968 CL175K0 Scrambler too.

[Stev-o]

Gorgeous restoration Flyin!

[MauiK3]

Love the green, of course

[HondaMan]

Boy, that one BELONGS in the family room! It's gorgeous! Great inspiration, too: I hope mine doesn't see these pix, or it might start crying and add more rust to it. Bob (of VJMC) came by with a Black Bomber for me to restore and had found 2 good NOS 350F1 side covers (in a white color I've not seen before) to 'start' my project bike with, and they both have the "350 Four" emblems! I only have 1 good side cover, and it's from a scrapped 350F that was Bacchus Olive. The original red ones are both broken.

The headers on mine will be a problem: I have 4 new 'trumpet' style mufflers (sitting in a box now 10 years) for it, but still haven't found suitable headers. Or any headers...

Where did you find those pipes?

[PeWe]

A really beautiful bike!
I was amazed the first time I saw a good looking Honda 350F painted in silver. The year was 1977.
Lots of mechanical details to admire.

[Flyin900]

Boy, that one BELONGS in the family room! It's gorgeous! Great inspiration, too: I hope mine doesn't see these pix, or it might start crying and add more rust to it. Bob (of VJMC) came by with a Black Bomber for me to restore and had found 2 good NOS 350F1 side covers (in a white color I've not seen before) to 'start' my project bike with, and they both have the "350 Four" emblems! I only have 1 good side cover, and it's from a scrapped 350F that was Bacchus Olive. The original red ones are both broken.

The headers on mine will be a problem: I have 4 new 'trumpet' style mufflers (sitting in a box now 10 years) for it, but still haven't found suitable headers. Or any headers...

Where did you find those pipes?

Mark,

The pipes fortunately came with the bike. They are made by Sanki I believe and are/were reproductions of the original ones right down to the muffler part numbers. Just no Honda logo. They have been out of production for a quite a number of years now. Both DSS and a few other US suppliers sold them back in the day.
I think someone had a batch made up and a number of parts distributors split the production. They then sold them for awhile until they were gone. It seems no one has stepped up to reproduce them again. Likely just not enough demand these days.
I think Carnivorous Chicken a member here has been looking for a set of them for awhile now.

[HondaMan]

Boy, that one BELONGS in the family room! It's gorgeous! Great inspiration, too: I hope mine doesn't see these pix, or it might start crying and add more rust to it. Bob (of VJMC) came by with a Black Bomber for me to restore and had found 2 good NOS 350F1 side covers (in a white color I've not seen before) to 'start' my project bike with, and they both have the "350 Four" emblems! I only have 1 good side cover, and it's from a scrapped 350F that was Bacchus Olive. The original red ones are both broken.

The headers on mine will be a problem: I have 4 new 'trumpet' style mufflers (sitting in a box now 10 years) for it, but still haven't found suitable headers. Or any headers...

Where did you find those pipes?

Mark,

The pipes fortunately came with the bike. They are made by Sanki I believe and are/were reproductions of the original ones right down to the muffler part numbers. Just no Honda logo. They have been out of production for a quite a number of years now. Both DSS and a few other US suppliers sold them back in the day.
I think someone had a batch made up and a number of parts distributors split the production. They then sold them for awhile until they were gone. It seems no one has stepped up to reproduce them again. Likely just not enough demand these days.
I think Carnivorous Chicken a member here has been looking for a set of them for awhile now.

Yep, CC has been a good source of info on these little bikes! He's ridden one/them a long time. I'm not sure yet how this one will turn out given the parts issues and how many are missing/bad on this one, but I don't want to make a cafe' bike of it. The first major stop is making the kickstarter's inner hole mount straight and in line with the outer hole, though I plan on e-starting it, in any case.

I do want to make it 100 MPH capable, which may take a Megacycle cam in the end, we'll see? The OEM porting isn't bad (unlike the 500/550 heads), but like the 1974+ 750s they can be improved some. Back when they were new I wasn't able to quite reach 95 MPH (indicated) on the 2 that came in for their 300 mile checkups, nor could Cycle magazine at the time. Since then I've seen one running 115 MPH at one time, sounding like it was going to 11k+ RPM, too. 'Twas a while ago, though!

Putting a Vetter on one made it top out at 80 MPH flat, which almost exactly matched the CB350K2 twin I also mounted one on. At the time it made me wonder how much HP those 2 engines actually made, as everyone seemed to think the 350F was a piker. From the internal design details it appears the only serious RPM limitation is in the cam chain's tensioner system that can stretch at higher RPM, like in the 550 engines. The valves are staggered (also in the 400F heads) for better flow patterns, something Honda could only have done effectively with their then-new NC machines that could quickly move to accurate angles to bore for guides. This hints at other hidden things, some which seem to resemble the screaming 350F DOHC racers they also made (but with non-streetable carbs, those flat ones). I'll bring up the details when I get the cases back & fixed: right now it's a make-it-whole battle.

[Prospect]

I bought some Avon speedmasters a few years ago.  They were 19' tires for a harley chopper.  Within two years they were cracking.  I now almost always use Shinko.