Bigdog Rear Tire 300MM Replacement

[Steve1028]

Thats interesting because I looked it up on both sites. Motox stipulates next to the size that it is a "non-radial". Don't understand that.
TireCave just lists it as a Radial.

I have sent an email to Avon asking the question. WIll let you know when they get back to me.

Kapt, since you sent an email to Avon, I sent one to Metzler, their 120/70-21 is non-radial too. I pretty much got a standardized reply, that I knew the answer to anyway, but here it is:

Hello

Thanks for the e-mail. So you know Metzeler introduced this 120/70-21 tire bias ply to the market back in about 2002 for the custom market. The idea was that the bike builders wanted a bigger wider front to match up with the new 240/040R18 and for other applications.

You may want to ask about mixing tire constructions. So you know there are always misconceptions about tires that never seem to go away and mixing bias ply front tires with radial rears is one of them. So you know companies such as Harley, BMW, American Iron Horse, Big Dog, and Yamaha, just to name a few, use and suggest bias ply front tires with radial rear tires for many applications. The statement that IS TRUE is that you should never mix radial front tires and bias ply rear tires on a motorcycle. Have a great weekend.

NA Metzeler Consumer Affairs
877 202-4993
Metzeler

 

[Steve1028]

Hell, after seeing the mileage Raywood's getting out of a front tire, I'm not sure it matters whether these fronts are radials or not! I just assumed the Avon front tires were radials like the rear, then I saw that 'non-radial' notation next to the 120/70-21. Now I have found out Metzler's front is bias ply too. I have always been under the assumption that radials ride better, get better mpg, and last longer too, thus the reason for me wanting a radial front tire as well. Dunlops front is a radial, but I'm not sold on that tire. Wonder if radial vs. bias really would make a difference in a front tire?

 

[KaptinAmerika]

Repsonse from Avon:

Curtis,

Thank you very much for the email and support of Avon tyres. The 120/70-21 is indeed a bias ply tire and is only available in bias ply. The '-' in the sizing indicates a bias ply tire. This is true for all motorcycle tires. A radial would be indicated by an 'R' in the place of the dash.

It is a common misconception that most modern motorcycles use radials when in fact a large number or bikes (nearly all Harley Davidsons) still run bias ply tires due to their tendency for better mileage over radials. If you send me the details on your bike I can tell you if the 120/70-21 would be a good fit for it.

Thanks again, have a great weekend!

Jared Peterson
Account Manager

Avon Tyres, North America
425-374-2125
330-928-0503 Fax
425-374-2125 Office

So I just found out that my front tire, MH20 - 91, is also Bias and not Raidial. You learn something new everyday.
I have sent a follow up email asking several questions and asking for a radial upgrade for each of our bikes Steve

 

[Steve1028]

I have sent a follow up email asking several questions and asking for a radial upgrade for each of our bikes Steve

Me first! Yeah right!!! Thanks for the info:2thumbs:

 

[barhopper]

I just wish I could figure out how in the hell Ray gets 22,000 miles out of a tire, and thats just to the wear bar. I take mine all the way to the bands in the tire.
Man if he could package that tip he could make a fortune.

When I saw you back tire, it looked like you had 20,00 miles on it. That thing was wore out for sure.

 

[KaptinAmerika]

When I saw you back tire, it looked like you had 20,00 miles on it. That thing was wore out for sure.

Dude if you looked at my How To on changing a 300 tire you would see what it looked like when I got home. I bet I wasn't a hundred miles from that thing popping on me.

 

[Raywood]

When I saw you back tire, it looked like you had 20,00 miles on it. That thing was wore out for sure.

I should have taken a picture of it. It's was down to the belts.

 

[KaptinAmerika]

So here it is straight from the horses mouth guys:

Curtis,

Happy to expand on my previous email.

1. Radials differ from bias ply tires in that they are more flexible. This flexibility gives the tire the ability to grab a bigger bite of the road. The down side: flexing in a tire also creates more heat build up. Heat build up leads to more ware, hence radials tend (not always) to get less mileage than bias plys. The difference can be minimal some times.

Avon has not gone over to making radials. Weather a bike runs radial or bias ply tyres is bases mostly on how the bike designers set the bike up for. A sport bike, with stiff suspension and a sturdy aluminum frame, works well with radials but would feel like an over sprung pogo stick on bias ply tyres. The opposite is true for a bike such as a Harley with softer suspension and a more flexible frame working well with stiffer bias ply tires but feeling like it has a speed wobble on radials. We simply produce tires to the size and design spec as is set by manufacturers, with our own design tweaks of course.

This also answers you second question. Some sizes are bias and other radials mostly because they bikes they are made for are designed to work with one or the other. Tire dimension also plays into this as well. Lower profile tires tend to be radial in construction.

3. There is no issue running a bias tire in the front of a bike, and a radial in the rear. However, if you reverse it and run the radial in the front, you will most likely have handling issues.

4. No manufacturer to my knowledge produces a radial in a 21" tire. They are only available in bias ply. Big dogs are meant to run bias ply fronts, you may have issues with a radial. I strongly recommend you stick to bias ply tires.

Thanks again for the support. If you have any more questions or would like even more detail, again just hit me back. Always happy to help out.


Cheers!

Jared Peterson
Account Manager

Avon Motorcycle Tyres North America
425-374-2125
Avon Motorcycle Tyres North America

So now you know, BDs are designed to run Bias in the front, or at least some models such as the K9 and Bull Dog.

 

[Raywood]

Great info Kaptn. Thanks for sharing. I've been very satisfied with my Avons and I'm sticking to them and my story!!!

 

[KaptinAmerika]

Great info Kaptn. Thanks for sharing. I've been very satisfied with my Avons and I'm sticking to them and my story!!!

If Venom's, which is what came on the bikes originally, are Bias and that was what BD designed the bikes for then why did Avon switch to Radial in the Cobra?
The 280 and 300 have only ever been offered in Radial not Bias
Ray what size is your rear tire?

 

[Raywood]

Is your Cobra Bias or Radial. If the Rear Cobra tires are Bias right now why did they go to Radial?

My rear is a Venom and it's got the R in it. Have no choice but to go to the Cobra now that it's replaced the Venom. Hopefully they will give the same high mileage.

 

[KaptinAmerika]

My rear is a Venom and it's got the R in it. Have no choice but to go to the Cobra now that it's replaced the Venom. Hopefully they will give the same high mileage.

Ok cause I remember you saying it was Bias when we were out at PS so I was confused

 

[erldawg]

My rear is a Venom and it's got the R in it. Have no choice but to go to the Cobra now that it's replaced the Venom. Hopefully they will give the same high mileage.

That is incredible that your getting that many miles on your tires Ray. When I got 10,000 miles on the Wide Glide tires I thought I was doing fantastic.....

So I went and looked again and the rear Venom on the K-9 is a R....

 

[Raywood]

Ok cause I remember you saying it was Bias when we were out at PS so I was confused

I don't remember saying that Kaptn. Must have had to much to drink. I've always known that the R meant radial on the tires. Sorry for the confusion.

 

[TCALZ06]

I've had the Avon Cobra on front and rear for about a year and a half. I got them when they first came out. No problems at all.

I can't get over 10k out of a rear tire. Maybe it's the heat in AZ. No burn outs for me either

 

[phatchopper300]

Looks like a great deal + free shipping http://www.rockymountainatvmc.com/productDetail.do?navTitle=Tires+and+Wheels&webCatId=8&navType=type&webTypeId=229&prodFamilyId=22949&listingId=&sizeAttr=5329&colorAttr= Not sure if these are the old model but still seems a good price. Just watch out for the manufacture dates.http://www.rockymountainatvmc.com/productDetail.do?navTitle=Tires+and+Wheels&webCatId=8&navType=type&webTypeId=229&prodFamilyId=22918&listingId=&sizeAttr=5595 Just sayin

 

[PacoPetty]

I just changed mine and the tire was $265 with free shipping from the motorcyclestore.com My buddy used the post on here to change it for me. He said it was really easy. Good luck!

 

[outdoorsman26]

when you guys say a tire is "old" and that is why its so cheap what do you mean?? the cobra series is only 2yrs old is that old???????

 

[KaptinAmerika]

when you guys say a tire is "old" and that is why its so cheap what do you mean?? the cobra series is only 2yrs old is that old???????

Its just means the tire has been discontinued.

 

[Buildem]

Just bought one a month ago off ebay. $253.00 shipped and had a local shop put it on for $40.00