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Cartires again questions

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This question only apples to sidecar rigs please. My 2017 RGU with Hannigan twin classic. The sidecar has a Car tire on it. work fine.

I am looking to go to a car tire on the motorcycle rear. This bike will not be ridden without the sidecar. In my search I get a lot of chatter about darkside but no mention of using the CT on a sidecar rig.

A 195/60-R16 car tire matches as prefect as it can get to the factory tire.  It is 3/5 of an inch wider and the same height. I do see were some run 195/55-R16 on the same bike without a sidecar. But the 195/55-R16 is a lower tire causing the speed to be off.

Has anyone used the 195/60-R16 on a Harley touring bike, and if so what tire. May is coming up and some rides planned I want to have it on before we take off.

180/65-B16                195/60-R16

Diameter inches (mm) 25.21 (640.4) 25.21 (640.4) 0 (0) 0%
Width inches (mm) 7.09 (180) 7.68 (195) 0.59 (15) 8.3%
Circum. inches (mm) 79.21 (2011.88) 79.21 (2011.88) 0 (0) 0%
Sidewall Height inches (mm) 4.61 (117) 4.61 (117) 0 (0) 0%
Revolutions per mile (km) 799.92 (497.05) 799.92 (497.05) 0 (0) 0%

 

I have NO EXPERIENCE with car tires on your rig.  I do have a fair amount o experience with car tires on my rigs.  Three issues...

1. Do you have enough clearance to run the wider tire?  If you have the room, do it.  It's a small advantage,,,better grip , longer wear

2. The slightly smaller diameter of the 195/55 R16 will give you a speedo error but not a big one but it has the advantage of effectively lowering your drive ratio.  That will give you a better low end at the cost of a bit of top end speed.  I seldom run wide open but you may and it will reduce your top speed.

3. A 16" motorcycle rim is slightly larger in diameter than a 16" automobile rim.  Makes no sense to me but it's a fact.  As you get larger in rim size this difference grows smaller.  16" is probably the smallest size where the darkside trick works.  I've seen folks try to mount a car tire on a 15" rim and it just doesn't seem to work.  Even at 16", mounting may be difficult.

There is also a difference in the design of auto rims and motorcycle rims.  The locking ridge/groove (it's a matter of how you look at it) is different but it seems to be a small issue and doesn't come into play.

Good luck.  The grip and tire life advantages make it worthwhile for me.

Al Olme Minneapolis, Minnesota

Thank you Al Olme.

Dealer will mount what ever I want on the bike. I would really like to stay with the same height tire for a few reasons. I have all the power I need plus some so no need to lower the ratio . There are a lot of riders without sidecars that run CT on the rear . It seems the bead issue is not such a concern. The 1905/60-R16 sure looks like the  way to go.

Dunlop SP Sport 5000 Symmetrical tire looks like a goof option for a higher end tire . But no mileage numbers for it                                                           The Hankook Optim0 H426 has a tread pattern that looks like it should work. 60,000 mile tire, 89 load index and designed for 5- 7 inch wheel .        All of those are Symmetrical tire witch is what would be the correct type of this.

 

I will keep reading and looking, it will happen just need to pick the tire now.

I have a P205 R60 16 car tire on the back of my 1998 Valkyrie sidecar rig.  The P205 is a little too wide and rubbed a little.  I think the next one will be a P195 width tire, but to keep the circumference about the same as the motorcycle tire I may go to a little higher profile tire.  The P205 is nearly identical to the OEM tire in that regard.

Smitty,

The wear index really isn't an issue.  Your rig is so much lighter than the car that the tire was intended for that it will last for MANY miles.  On my rigs the car tires (both front and rear in my case) get changed out because they get hard over time rather than wear out.  The only time I've worn out a car tire was because of an alignment issue.

Al Olme Minneapolis, Minnesota

Speedometer correction can be handled with a TSS MasterTune.   This is a fuel/map tuner built by the folks that make the Harley SE Race Tuner.  But, I like the MasterTune better - it is much more flexible with its capabilities.  The Race Tuner is limited by the EPA in what it will allow the tuner to achieve.  The MasterTune has a parameter to adjust for changes in the indicated speed (speedometer correction).  I tuned a 2010 Ultra Classic a few years ago that was running a car tire and was able to correct the speedometer to within a couple MPH of the customer's GPS.

H-D does not endorse MT (they want to sell their products, naturally), but their existing tuners are for production/street only tuning.

Hope this helps,

Bud...

Learned on thing in all this research . The rim protector tire do have a wider bulge on the curb side. That could cause an issue for some. Tired of all the home work went with a Hankook 426   190/60R16 205 would work but was wider than I wanted.

My tuner would calibrate for size Just wanted to keep it as close as possible. Soon as the rear wears out It will get mounted .HA dealer will mount it.

The local Car tire place would also long as it was going on a sidecar rig.  But for a Bike alone they will not do it. Waiting now for a phone call . They are install my reverse gear set today.

 

Late to this thread and since you've already purchased your tire I will refrain from commenting other than to say that the Hancook Optima is a fine choice and the 195/60-R16 should mount up OK and fit OK.  (That's the size you meant to type, right?) There are other car tires in that size that are longer wearing and others that are grippier, but the Optima is a good middle ground.

But I'm curious about your bike.  I've never heard of a RGU.  Is that the name of the manufacturer or a motorcycle model name?  In short, what is it?

Quote from DRONE on February 28, 2019, 12:15 am

Late to this thread and since you've already purchased your tire I will refrain from commenting other than to say that the Hancook Optima is a fine choice and the 195/60-R16 should mount up OK and fit OK.  (That's the size you meant to type, right?) There are other car tires in that size that are longer wearing and others that are grippier, but the Optima is a good middle ground.

But I'm curious about your bike.  I've never heard of a RGU.  Is that the name of the manufacturer or a motorcycle model name?  In short, what is it?

Always interested in what other have to say. We can all learn something . Input often gives another way to loo at things.  This Rig Is a Harley Road Glide Ultra with a Hannigan Twin Classic sidecar .  While it seems many run a 205/55 R16 on bikes without a sidecar the 195/60R15 size wise is almost a prefect match. So many of the tire I looked at had tread patterns that were different left and right of center. Also Tires in 195/60R16 are limited. After beating my head about it I hot the send key on the Hankook 426. That does not mean I am not open to trying others. I ride so no doubt tires will be replaced . I had considered a Michelin X-Ice but tire dealer did not think it would be a good option and she does know here stuff.

Bike is sitting at dealership now , just had the Reverse gear set installed. I may have them install the new tire now rather than wait for the current tire to wear out. This is what it looks like.

 

 

 

Uploaded files:
  • RGUsidecar.jpg

Sharp, good looking rig, like the color matching.

Doubt if there is anyone who knows more about going to the Darkside safely than Drone. He is a great resource for we sidecarists.

 

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