Topic: The tire size for 1978 cb750k

[Black Hercules]

Hey! guys I have a problem with the right size rear tire for 78 cb750k. The tire needs replacing A.S.A.P and I dont know exactly the  proper
size. The tire that's on there now reads 4.50/85 H17, I dont know if im suppose to go with (130/90 17 or 120/90 17), the rim size reads
2.50x17 and Im thinking with going with maybe Dunlop D404's or Bridgestone bt45's . So if anybody has info on correct size please help
thanks.

[jdpas29]

i've got dunlop 404s on mine and i like em.  i think that tire is a 120/90  17  also known as a 4.5 H17 or something like that.

[kghost]

If its a 1978 its not a K2.

Here is some info from a quick google search....read and enjoy 

http://www.ridegear.com/rg/sizingcharts/Motorcycletires.html

110/90 = 4.00/4.75 on the rear.

120/90 = 4.50/4.75 on the rear.

Personally I run a 120 which is a tad oversize for a  1972 K2 rim but it works 

[seaweb11]

I take my wheel into the dealership tell them the brand of tire I want, and they put a tire on it

I have no idea what size it is...should I?

......and mine is a 78 K8

[kghost]

I take my wheel into the dealership tell them the brand of tire I want, and they put a tire on it

I have no idea what size it is...should I?

......and mine is a 78 K8

  You expect us to buy that statement? 

[nteek754]

Hey guys  Im running 130/90/16 and loving it I love having a good fat sidewall keep mei n line literraly but some guys never want to do that they want to be stock  oh mine is a 1973 750K now coarse sock back in the day it was what I think 400 18  and my front is  110 19  I thinkI have stuffed a fat one on front 325 or soo have fun seven fifty four ever Craig in Maine

[eldar]

I run a 110/90 19 on the front and A 130 or 140/ 90 17 on the rear. looks pertty good and works good too. I have a 78K.

[bryan]

I run a 110/90 19 on the front and A 130 or 140/ 90 17 on the rear. looks pertty good and works good too. I have a 78K.

I'm running the same size tires on my k8.  How well does a 140 rear fit? 


Just don't get a 120 rear tire!

[eldar]

well I cant remember exactly what it is but the rear fits very well. Looks great. Not too wide or too thin

[Black Hercules]

 thanks ! jdpas29 I sounds like d404's is the direction that Im heading for and the size sounds right to me. Thanks once again

i've got dunlop 404s on mine and i like em.  i think that tire is a 120/90  17  also known as a 4.5 H17 or something like that.

[newday777]

I know this thread is old....
But does anyone know if these will fit on a 78K without clearance problems?? I know they are radial tubeless.
Thanks

Front: 110/80R19 Tubeless

Rear: 150/70R17 Tubeless

[Rosinante]

I just have a wimpy 120 on my K8.  There appears to be plenty of lateral room to go bigger.  On cars, I avoid tread patterns much wider than the wheel because this prevents the tire from changing its shape in turns.  Wide tires on narrower wheels is a mistake, I think, even though it is thought to increase the size of the contact patch.  Incorrectly so.  But....motorcycles are a completely different animal, I imagine.