The International CBX Owners Association

I have Bridgestone Battlax BT 45s on my other two bikes, 76 GL1000 and 83 CX 650 Turbo and love them to bits.
Time has come to replace some old Metzelers on my Z and wonder before ordering, which are the Battlax BT45 sizes, closest to original.

From the forum I have gathered the FRONT to be 100/90 R19 57V, but not sure about the rear.

Can you help?

Aris

Aris:

You are in somewhat of a predicament. The original tire on the rear of the 1979 and 1980 CBX was a 4.25-18. For the Prolinks, Honda changed to a 130/90-18 , which is equivalent to a 5.00-18.
The 1979 CBX had the narrowest rear rim of all models.
So in order to stay as close to original as possible, you would have to fit a 120/90-18. I am not sure, if the BT45 of that size comes in the correct speed rating that you want. ( I believe it is H rated)
I know many have switched to a 130/90-18, but the BT45 only comes ina 130/80-18.
I personally use Conti tires on my CBXes, but many actually swear by the Bridgestone Spitfire S11, which offers the correct sizes, I think.

Mike thanks for the info.

I have just checked and Battlax BT45 120/90-18 most certainly exists with a V rating and is referred to as 120/90 R18 64V.
So to keep it simple, and in line with the bike's original (that is puny) swing arm, I guess this will be the one.

Cheers, Aris

Kool_Biker wrote: Battlax BT45 120/90-18 most certainly exists with a V rating .. I guess this will be the one.

Cheers, Aris

Ooops

Existing is one thing, importing into Greece is quite another ...

But I CAN find 130/80 R18 66V locally, and my tyre shop swears is fine for my 79.

Any comments chaps before I go ahead and order? Is the rolling radius appreciably different?

Thanks, Aris

Aris: You should be fine. The sidewall height of a 120/90 is 4mm higher than a 130/80 (130 x 80% = 104mm; 120 x90% = 108mm) This means a travelled length of 2091mm per wheel turn for a 130/80 and 2116mm for a 120/90

Thanks Mike!
Aris

I have used 4 sets of Dunlops GT 501 on my 79 and 80 CBX and no problems but I thought that I might try something different and put a Michelin Pilot Activ on my 79.In the meantime I had ordered two 170/60 18 Dunlop Roadsmarts for mu 94 and 95 CB1000.After some weeks I was told that they are no longer available and the Roadsmart 2 is only available in a 160/60 18.I therefor ordered 2 Avon Cobra for these bikes in a 180/55 18 and really like these tires .Than I thought I might try the Avon Roadrider on my 80 CBX and like them alot too(grip and looks) as I had only 90 miles on the Michelin Activ my dealer agreed to change that one for another Avon Roadrider as well(I spend already $1500 on tires at the MR Cycle dealer in Ashville)I went back to a 120/90 instead of the 130/80 I had on the bikes before.It is amazing that there can be 10 mm.difference in size between the same size tires bought from different brands .On the front I always use the Metzeler Lazertec and really like them.At the moment only AVon and Metzeler give ALL the measurements in their brochures what can be very helpfull.I have ruined a front fender with the wrong tire in the past and have now just a 100/90 in the front.Tires look very skinny on a CBX but thats the way it is on older bikes.Have a great summer!

The new Battlax rubber is safely on the bike, and I can't wait to go for an inaugural ride!
What pressures do you use with these tyres for, er NORMAL* riding?
Surely with modern rubber things must have moved on from the original Honda recommendations.
Cheers, Aris

*Absolutely not intending to open a new debate, pls, something to start me off

34 F/36R or 36F/38R is fine for your '79.

Dave

Thanks Dave!
The ride will have to wait though, as the weather here in Athens has suddenly turned to cloudy / light rain ...

Which is to say, absolutely and utterly OK, compared to the tornados the US has experienced lately over Texas.
Seeing articulated lorries lifted hundreds of feet in the air, just like matchboxes, is simply incomprehensible over here.

I do hope everyone in our great community is fine.

Aris

Amazingly, no deaths were reported in the latest round of weather in Texas. This has been a quite active season so far in the south.

I think you'll like the tires - they are far more tire than the CBX came with 30 years ago!

Dave