Avon Cobra 150/80/17

[Battersea]

Maybe on early models, Battersea, but the 2012s and 13s are sporting 130/80 17 Dunlops.

ooops - I only looked at the RK which is still on 16" - Ultra's on 17".

Fitting a 65H on an Ultra at 413kg just makes a mockery of the ratings surely, or is it synonymous of the tractor like performance.

If a 65H is OK for an Ultra you would think it would be OK for a Rocket, no? What are those Dunlops like? I hated D402's on my Fatboy.

 

[TriumPhil]

Never ran those Dunnie Elites, but they seem to mostly earn high marks.

The new B'stone Exedra Max 130/70 17 has a lower load rating of 62 and has a W speed rating. An engineer from B'stone has essentially said to "rock on" and not to fuss over the load rating, so I'm going for it... no guts - no glory!

 

[Battersea]

I was interested to know what effect the different tyre combination had on the geometry of the bike so I sketched something up, I have always found it easier to comprehend things when its graphical. Obviously this is a very simplistic comparison but it does give some idea.

Phil, that 130/70 changes the head angle and 'trail' quite a bit, especially if using with a 240/55. I'm using the word 'trail' although not quite in context, I don't know the distance between fork legs and headstock so cant calculate true trail.

I'm not too hot on the effects of fork angle change other than steeper castor angles give straight line stability at the expense of slow speed stability and vis versa.

 

[joey fletcher]

Hey Guys.

I would be very careful about the lower load range on the front tire...Speed and wind screens add down force to the front tire...

To much weight on the front tire will cause damage to the belts in the tire causing a wobble to start in the steering...

Last Jan. 2012 I bought me a 2009 K1200 LT Trike it was used with 12,000 miles on it. The trike was built by Hannigan at their factory and was own by a lady...her husband got sick and could not ride his Gold Wing anymore..so they sold both trikes..

She did tell me that she had hit a truck tire recap and damaged one of the floor boards and had it replaced..Everything looked good on the trike

The trike was at a trike dealer...there was a new front tire on it...still had 95% of the vacuum tits on the tire and a new battery.

So I bought it and rode it home...855 miles...75 to 85 mph....I hit 110 just for a few seconds...half way home I started to feel a slite wobble in the front end. Once home the wobble was bad at 40 mph but smoothed out above that speed.

I checked the alignment...made some adjustments...and no change. After 3 weeks of working on the trike I was doing some more checking and seen a odd bald name on the new front tire..I called the tire rep and he said that tire was for a sport bike and not an K1200 LT..and I should not ride it anywhere with that tire on it.
I took off the front tire and had the tire replaced with the correct bridgestone...

The Trike was absolutely perfect after that...I think the old tire was rated for 598 lbs...

So be very careful with under rated tire on a heavy bike...I sold the trike 2 months later....I did not like riding a Trike...and never will

Oh....I do have a C/T on a rim and a M/C tire on a rim too
Going to put the C/T back on after the trip to MV

 

[TriumPhil]

I was interested to know what effect the different tyre combination had on the geometry of the bike so I sketched something up, I have always found it easier to comprehend things when its graphical. Obviously this is a very simplistic comparison but it does give some idea.

Phil, that 130/70 changes the head angle and 'trail' quite a bit, especially if using with a 240/55. I'm using the word 'trail' although not quite in context, I don't know the distance between fork legs and headstock so cant calculate true trail.

I'm not too hot on the effects of fork angle change other than steeper castor angles give straight line stability at the expense of slow speed stability and vis versa...

Good input, Sir. I run Progressive 440 shocks in the rear which are 1/2" lower than the OEM shocks. That pretty much exactly offsets the 240/55's taller aspect ratio. Also, I have ridden my friend, IFT's, Silverback with this setup and it is by far the best riding and handling R3 I have experienced out of many others.

I'm locked and loaded, especially with the reassurance that came, unofficially, from a B'stone engineer. These tires are engineered and built to tolerances which somewhat belie their load and speed ratings. Remember, the rear tire has not been formally homologated for the R3, yet it is a substantially superior performing tire to the stock Metzeler for my purposes. I'll let you know my impressions wit the new tire combo just as soon as I can.