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Car Tire Model Input - BF Goodrich Comp 2 vs Bridgestone DriveGuard Plus (or other?)

drakontas

New member
I've been an MOA member for a few years, but this is my first post here -- apologies in advance if I've picked the wrong place to post this.

I'm planning to put a car tire on my 2011 R1200RT. The goals here include longer time between tire changes, better handling in rain, and better handling on occasional dirt/gravel detours.

Based on what I've heard from others, together with my 17" wheel size, I'm currently considering the 205/50/17 versions of the BF Goodrich Comp 2 All Season (MSRP $165) and Bridgestone DriveGuard Plus All Season Run Flat (MSRP $265).
I've already ordered a spacer and slightly longer replacement bolts to handle the wider tire (vs 180/55/17 stock).

What opinions can folks share between these two tires? Is the extra $100 for the run flat feature worth going for? Does the higher mileage rating advertised for the Bridgestone (65k) vs the BFG (45k) manifest in longer life / higher miles on the road when used in this way?

Are there other tires you've used that you'd recommend above these two?
 
It took me a bit to think about this. Is a car tire going to work in a motorcycle application? Car tires, and the two that you suggest, have a square profile with distinct radii at the shoulders. That's going to make for some very unusual handling characteristics. I'm guess it's going to make it very hard to lean the bike over for turns. Maybe I'm missing something.

Welcome to the forum as well!!
 
Welcome to the forum!
Car rims and motorcycle rims are very different. The beads are not the same. The motorcycle tire will not seat properly. And you run the risk of the tire separating from the rim at the most inconvenient time; like going around a corner.
This is why no reputable tire installer/dealer will mount a car tire on a motorcycle rim. Too much legal exposure.
Also, you might want to check your own legal exposure if you cause harm to somebody because you modified the handling characteristics and safety design of the motorcycle. An ambulance-chasing lawyer would have a field day with that.
Check with your insurance company about that.

Good luck!

Joe
 
Thank you both for your reflections and concern for safety! Running car tires on motorcycle rims can be done safely and these two models of car tires both have precedence for being run successfully and safely. The question isn't whether car tires can be run on bikes or whether it can be safely -- instead, I'm looking for feedback from folks who have run these two tires about how these two in particular compare to each other. I realize it's a relatively small percentage of riders who run car tires, but I can see from forum searches that it comes up here once in a while so I'm hoping someone who has run these might see this post.
 
, better handling in rain,

I would think there's less traction in a curve when you're up on the very small contact patch at the edge of a car tire.
You can see it in the first part of the video in post #5.
 
The FJR community has many riders with many miles riding on the Darkside. On the FJR forum there are a couple of lengthy threads on the subject. This one is on FAQs: https://www.fjrforum.com/threads/darkside-faq.124275/. Last time I looked on the other general info thread on the same site (221 pages) (https://www.fjrforum.com/threads/going-to-the-dark-side.141913/) they were claiming over a million miles of Darkside riding without an incident attributed to the car tire on the rear.

I ran a car tire on the rear of my FJR for about 15,000 miles. It takes more effort to initiate a turn and requires continuous input to maintain the lean and turn. This is not significant effort and quickly became unnoticeable. The bike will tend to follow irregularities in the road, such as cracks, more than with a bike tire, but is less likely to step out on a tar snake. Overall handling is not as good as with a bike tire for an hardcore twisty rider and is most noticeable in sharp twisties that need rapid transitions. The handling on my bike remained predictable and stable and never became scary. I used mine on long trips that would have required a tire change mid-trip.

I have never heard of a bead separation from a rim and the thread referenced above has scores of riders with many miles of experience. It also shows that a car tire has a larger contact patch than a bike tire even in a corner.

The Darkside isn’t for everyone but I think there is enough on road experience to demonstrate that it is not unsafe.
 
Thanks for the input, akbeemer and Lee.

Yes, there are vast numbers of miles ridden both collectively and by individual riders over decades demonstrating that it can be done safely with the right tire size, tread, and use case. You would probably not choose a car tire for a track day or tight curvy mountain road, but a car tire can be a good choice for a case where someone expects to do thousands of miles of relatively straight riding. As the video shared above shows, picking the wrong tire width (for example) or trying to use a car tire for a type of riding it's not suited for can increase risk -- but would be is incorrect to suggest that all car tires are "too wide" or "too square" to be operated safely.

But, again, I must reinforce that the purpose of this thread is not to debate whether it can be done or whether it is safe to do. That topic has been beaten to death for years (decades), and the spectrum of perspectives is well established -- we're not going to solve anything by reinventing the wheel here (pun intended).

This thread really, truly, is just seeking informed perspectives from people who have ridden either or both of these two specific tires, and their thoughts on the tradeoffs between these two tire models.

I appreciate the nudge about the FJR forums, akbeemer -- I'll look around for other places to ask the question, too.
 
Thanks, 20774 -- I did some searching on bmwmoa.org using the approach you shared for "BF Goodrich", "Comp 2", and "Driveguard" and found a very small number of comments including those topics. I have found some great comments about these tires on the FJR thread shared by akbeemer though, so I think I'm close to my answer.

For anyone finding this later -- comments suggest that both are great tires for this use case, but the Bridgestone may have better traction / tread on its corners vs the BF Goodrich Comp 2, which may provide better handling in turns. Together with the run flat feature and the higher 65k vs 45k mileage rating, I'm leaning toward the Bridgestone Driveguard Plus at the moment. Bridgestone Weatherpeak is emerging as a strong contender, however.

Edit for completeness:

The full range of tires that made "close to final cut" so far are all in the 205/50/17 size and include:

BF Goodrich Advantage Control
BF Goodrich Comp 2
Bridgestone Driveguard Plus
Bridgestone Weatherpeak
Michelin CrossClimate2

In terms of traction, CrossClimate2 looks best for a stronger bias of dirt/gravel/mud, while Comp 2 and Driveguard Plus seem best for a stronger bias of clean road. Advantage Control and Weatherpeak seem more balanced between the two, with Weatherpeak looking like it may have slightly better handling in "unclear terrain" (2 continuous clear channels along the tread in Weatherpeak vs 4 continuous clear channels along the tread in Advantage Control).
 
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