Author Topic: street legal tires for road racing cb750  (Read 3848 times)

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Offline gschuld

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street legal tires for road racing cb750
« on: September 14, 2015, 02:28:03 pm »
I have a fresh set of AM22/AM23 race tires on dedicated alloy 2.5 rear, 2.15 front rims/Buchannan spoke wheels/factory hubs.  I have a separate set of wheels, 3.5x18 DID aluminum rear, 2.5x18 DID aluminum front, on identical factory drum rear, dual disc front hubs with Buchannan spokes.  I'd like to put on a street legal set of tires that can be used occasionally on the street, dyno runs, and potentially the track if they would be an improvement over AM22/AM23 tires in the rain(not the Avon race tire's strong suit I hear).  They would also be a worst case backup plan if I damage an Avon race tire and don't have a replacement on hand.

So I'm looking for recommendations for street legal tires in a 130 to 140 rear/100 to 110 front x 18 for both.  I'm certainly not looking for high mileage capable tires, but something that would do reasonably well for track days, racing in the rain?, etc.

Heidenau, Dunlops, BT45s, Avon Roadriders, what makes sense?

Thanks,

George

Offline turboguzzi

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Re: street legal tires for road racing cb750
« Reply #1 on: September 14, 2015, 03:04:33 pm »
george, you run the risk here of getting an "engine oil" thread like response, i.e. everyone's got a liking... add into th emix also michelin macadams, conti TKV,  if you want..

my choice would be BT45s, i think they are among the only ones to have dual compound rears, softer on the edges

but i bet youll get 10 different reponses, lets see  :)

Offline bwaller

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Re: street legal tires for road racing cb750
« Reply #2 on: September 14, 2015, 03:26:20 pm »
It may have been me that made you think Avon race tires weren't the best rain tires. They are really quite good, just not on a par with full on racing rain tires. Those get destroyed when the track is dry.

Obviously Avon race tires aren't what you need for the street, but you'll be hard pressed to find a street tire that outperforms Avon race tires in the wet.

From the outside looking in, Heidenau's are better suited to lighter bikes???

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #3 on: September 14, 2015, 03:28:31 pm »
george, you run the risk here of getting an "engine oil" thread like response

my choice would be BT45s, i think they are among the only ones to have dual compound rears, softer on the edges


Yeah I know, I certainly wasn't expecting everyone to sing the same tune.

Do you think BT45s would be better than Am22/23s on the track in the rain?



Brent,
 
I must have misunderstood you regarding the race Avons in the rain.  That's good to know that they are good in the rain.  They certainly seem to have enough water shedding capacity.

George
« Last Edit: September 14, 2015, 06:35:51 pm by gschuld »

Offline Haybus

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Re: street legal tires for road racing cb750
« Reply #4 on: September 14, 2015, 06:18:51 pm »
I've only ridden on my 22/23's a couple times in the rain, but I was surprised how well they performed. Cheap they're not, but they seem to be holding up quite well for my first season. Very happy with them and doubt I would stray away from them on a future purchase.

Alan
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Offline teebee67

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Re: street legal tires for road racing cb750
« Reply #5 on: September 15, 2015, 02:16:24 am »
Avons are good in the wet but, in my opinion, Heidenau's are better in the wet and just as good in the dry. They are also cheaper and last longer and are fine on bigger bikes.
I'm only old on the outside.

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #6 on: September 15, 2015, 06:27:13 am »
Teebee67,

Interesting.  I haven't heard any first hand reports before on using the Heidenau race tires on the heavier and more powerful cb750 racers.

Avons seem to be far more popular here, but I am very interested to hear more about your experience with the Heidenau tires.  If you don't mind sharing, what model and sizes tires are you running and on what rim sizes.  Have you run both Avons and the Heidenau tire to compare them?  It might be interesting for me to run a set of Heidenaus on a seperate set of wheels for some back to back comparative testing with the Avon AM22/23 tires at a track day at some point in the future.  Avon race tires can be difficult to get your hands on at times it seems... (thanks Brent ;) ).

It would also be good to know the comparative ease of availability of Heidenau race tire vs Avons up in the northeast US.

George

Offline turboguzzi

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Re: street legal tires for road racing cb750
« Reply #7 on: September 15, 2015, 08:51:25 am »
Heidi have the K64R which is a 130/70-18, big enough for any 750 IMHO,

it's the K65R that might be too small, still 120/90-18 is not that narrow...

Offline simon#42

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Re: street legal tires for road racing cb750
« Reply #8 on: September 15, 2015, 12:57:59 pm »
if we are talking about road tyres i would go for either the bt45'5 or the conti classic attacks , the 45's are very good in the rain.

Offline Old Scrambler

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Re: street legal tires for road racing cb750
« Reply #9 on: September 15, 2015, 03:31:41 pm »
George..........the BT45s work very well on wet salt ;D ;D ;D

My friend Kevin should be able to get Heidenau donuts at a good price.............he is a direct dealer...........scramblercycle.com
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Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #10 on: September 15, 2015, 04:01:42 pm »
So the Heidenau K64R race tires come in the size below according to their website.  "63H" refers to the speed and load rating, with 63 being the load rating(600lbs) and H being the Speed rating (124mph).  Does that make sense? A dedicated non DOT road race tire with a 124mph speed rating?  I think Mike Rieck will agree that the engine he is building for me will propel a 425lb track bike to well over that speed on anything but the tightest track.  Are the Heidenau K64R race tires's speed rating ...under rated?

Brent, perhaps the K64H Heidenau Race tires are not necessarily more suited to lighter bikes(the K64Rs are load rated for 600lbs), but more specifically to less POWERFUL bikes with lower top speeds?

Heidenau K64R race tires: 130/70 – 18 M/C 63H TL (1st photo)


Regarding street tires, Bridgestone BT45V DOT street tires(2nd photo), on the other hand are V rated (up to 149mph)  Standard (non V)BT45 tires are H rated(124mph)

Avon Roadriders, DOT street tires(3rd photo), are also V rated across the range.  They also seem to be a well respected performance street tire, but perhaps not as good as the BT45Vs.

George
« Last Edit: September 16, 2015, 02:59:08 pm by gschuld »

Offline bwaller

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Re: street legal tires for road racing cb750
« Reply #11 on: September 15, 2015, 06:02:37 pm »
I feel myself biting my tongue on those Heidenau. Many lightweights in our assn. use them and love them. I wonder if we don't get all the available tires in Canada.

I was asked to ride an endurance race in the rain on BT's and I was pleasantly surprised. I have Avons on my 750 street and they are good tires, probably not the Bridgestone equivalent though.


Offline teebee67

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Re: street legal tires for road racing cb750
« Reply #12 on: September 16, 2015, 01:05:08 am »
George, I'm not sure about speed ratings - are they the rating for sustained speed rather than top speed down the backstraight? I don't know I am just asking the question. I will check the tyres I run today and post details for you.
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Offline Retro Rocket

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Re: street legal tires for road racing cb750
« Reply #13 on: September 16, 2015, 02:26:53 am »
continental classic attacks were specifically designed for classic racing, worth checking out, also the conti Road attack CR,s  both in the sizes you are looking for...

Classic
http://www.continental-tires.com/motorcycle/tires/motorcycle-tires/classic-classic-racing/conticlassicattack

Road race and road
http://www.continental-tires.com/motorcycle/tires/motorcycle-tires/classic-classic-racing/contiroadattack2cr

750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
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Offline turboguzzi

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Re: street legal tires for road racing cb750
« Reply #14 on: September 16, 2015, 03:01:55 am »
ratings are sustained speed, not a few seconds at the end of the straight... and BTW, my GPS tracker says that on my 90 rwhp Gpz750/810 I never get to more than 125 mph even in circuits with decent straights like Magione or Vallelunga...

in short, george, you seem to be worrying too much over this. unless you are a Brent or a Tyler in raw talent, tires are not what is going to hold youo back :)

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #15 on: September 16, 2015, 04:41:12 am »
Good information.  Thanks.

Until I see far more widespread success with Heidenau race tires on big bikes, I'll stick with the Avons.  The  only benefit seems to be price, which is not my primary concern, especially for such an important part of the bike.  Avon 22/23 tires are the dominant race tires on bigger bikes over here, I think I'll stick with that.

Though they seem to have a big following, unless the Continental road attack tires(photo below), either street or race versions, are clearly superior to Avon 22/23s race or BT45v street tires, I'd prefer not to use them simply because the super modern tread pattern puts me off.  I know that's probably silly, but the vintage aesthetics make a difference to me.

It sounds like BT45v tires for street, dyno runs, backup tires to the Avons are making to most sense for me.

George

« Last Edit: September 16, 2015, 03:03:45 pm by gschuld »

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #16 on: September 16, 2015, 01:17:22 pm »
ratings are sustained speed, not a few seconds at the end of the straight... and BTW, my GPS tracker says that on my 90 rwhp Gpz750/810 I never get to more than 125 mph even in circuits with decent straights like Magione or Vallelunga...

in short, george, you seem to be worrying too much over this. unless you are a Brent or a Tyler in raw talent, tires are not what is going to hold youo back :)

I get what you are saying.  I am handicapped by the fact that I am putting together the parts that create a race bike that will be capable of performance FAR exceeding my track experience level.  But I want to be confident that the tires I use are up to the task.  Brent's blue bullet routinely hits mid 130s at Mosport and I believe JohnN has seen low 140s on his 750.

My power to weight ratio should be in the range of both of these bikes(it's a big motor).  My point is that even though it may take a while to get enough practice, and courage, to press the bike that hard, I want to make sure the bike is up to it.  Plus, it is VERY likely that I will request the help of one or several experienced riders to run my bike early on at track days and help me get it dialed in as they would be far more tuned in to what needs adjusting than I would be.  I wouldn't consider asking anyone to test my bike unless I was confident the bike is set up right equipment wise.

Most sources state the speed rating to be the maximum speed the tire is rated for at the maximum load rating and at the maximum rated tire pressure.  I can't say that I'm comfortable with the idea of using a tire that is rated for 120mph when the bike is capable of over 140mph on a high speed course.  Avon AM22/AM23S are V rated for 149mph and are very proven race tires, so why take the risk on a heavy, powerful bike?  To save a bit on the tire budget?

I can certainly justify the cost of the Avons if my assumptions above are accurate.  I have a set already.

George

« Last Edit: September 17, 2015, 06:05:00 am by gschuld »

Offline simon#42

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Re: street legal tires for road racing cb750
« Reply #17 on: September 16, 2015, 02:52:40 pm »
i always found the am23 a very poor choice for quick heavy bikes , on a 750 yamaha it was fine for two or three laps then the performance would go down hill rapidly , the dunlop [ which is now unavailable ] was a much much better tyre .
i think the classic endurance racers in europe seem to favour the continental now days . you could pm mec on this forum and ask his advice as he is involved with one of these teams and will know better than me .

Offline bwaller

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Re: street legal tires for road racing cb750
« Reply #18 on: September 16, 2015, 04:34:38 pm »
My good friend successfully races a beast of a Katana, wears the #1 plate and races with AM22/23's. I think they look odd on that bike but you can't argue with his success. I've never seen him fall off that bike. He did crash his Gixxer last weekend on new rain tires.
 

Offline simon#42

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Re: street legal tires for road racing cb750
« Reply #19 on: September 17, 2015, 02:33:07 pm »
i checked that out , and i disagree .... that bike looks fine ! . his lap times are not a million miles from your 500 times though brent , i would have expected a much larger difference .

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #20 on: September 17, 2015, 04:10:00 pm »
his lap times are not a million miles from your 500 times though Brent, I would have expected a much larger difference .

Because Tyler is just that fast on the blue bullet ;D 

Regarding performance street tires, I am a little surprised that no one has mentioned the DOT Avon AM26 Roadriders.   The AM26 race version with soft compound are pretty popular with the lighter bike crowd from what I saw at Mosport.  I have heard many reports of the DOT Roadrider tires being very grippy for "spirited" riding on the street and reportedly do well in the rain.  They also have a good selection of sizes to choose from.

Regardless, I take it that the BT45v tires are favored over the Avon Roadriders as performance tires?

George

Offline bwaller

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Re: street legal tires for road racing cb750
« Reply #21 on: September 17, 2015, 05:04:47 pm »
I thought I mentioned that I use those Avons on my street 750. I like em.

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #22 on: September 17, 2015, 06:21:20 pm »
Oh right, I forgot :).  If you were in my shoes and wanted a set of DOT tires that could be used on a separate set of 2.5x18 and 3.5x18 wheels(other set has WM3/WM4 with AM22/23 race tires) that could be used for occasional rides on the street, dyno runs, and potentially wet track days and emergency spares for race days, what would you put on?

Avon Roadriders? Bt45Vs?  Something else?

George

Offline bwaller

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Re: street legal tires for road racing cb750
« Reply #23 on: September 17, 2015, 06:57:41 pm »
BT's

Offline gschuld

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Re: street legal tires for road racing cb750
« Reply #24 on: September 17, 2015, 07:15:31 pm »
That's what I figured ;)

Good enough for me.

George