Author Topic: 130/90/18 or 120/90/18 new rear tire on my K1, which ?, any opinions ?  (Read 9666 times)

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Offline Spanner 1

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I want to put new Dunlop 404's on my 750 K1, front would be 100/90/19" , but not sure about back tire, 120 or fatter 130....any thoughts, opinions ?
« Last Edit: May 18, 2009, 11:30:04 AM by Spanner 1 »
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Offline swan

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110/90 18's for my CB750's
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Offline Inigo Montoya

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From what I have heard, the earlier K bikes had narrower rims than the 77/78K. Consensus seems to be that the 110 is best with 120 the edge. Now this is for supposedly proper handling. I feel tire design effects this though. Also a 110 from bridgestone might not be exactly the same as a 110 from dunlop. Check with each manufacturer as tire tech has changed and what honda listed in the 70s may not be completely accurate anymore. 

Offline MCRider

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From what I have heard, the earlier K bikes had narrower rims than the 77/78K. Consensus seems to be that the 110 is best with 120 the edge. Now this is for supposedly proper handling. I feel tire design effects this though. Also a 110 from bridgestone might not be exactly the same as a 110 from dunlop. Check with each manufacturer as tire tech has changed and what honda listed in the 70s may not be completely accurate anymore. 
I'd say that's right. The older rims were 2.15s, max tire is 110 per the book. 120 would work, but I wouldn't do a 130 without a rim change to a 2.5.
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Offline Spanner 1

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Thanks, all , for the info..........
Anyone else ?
« Last Edit: May 18, 2009, 11:30:29 AM by Spanner 1 »
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Offline mrblasty

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Too wide a tire will get "pointy" at the center of the tread which will lessen your contact patch with the road. 
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Offline turboguzzi

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Too wide a tire will get "pointy" at the center of the tread which will lessen your contact patch with the road. 

+1

Offline Old Scrambler

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Depending on the tire brand and profile, the 120 may touch the chainguard. The 130 will require a notch in the chainguard.
Dennis in Wisconsin
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Offline Kevin D

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I had 110 spitfire and replaced it last year with 120 battalax. No fitment or clearance problems. I have about 1/8" to the brake stay arm.
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Offline andy750

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Too wide a tire will get "pointy" at the center of the tread which will lessen your contact patch with the road. 

+1

+2 been there and see it. The 110 works so much better in the corners.....lean, lean, lean....if you are only cruising down the highway and what a fit tire look go for the 120 but expect it to wear more in the center.

cheers
Andy
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Offline Spanner 1

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Real life answers....I love it , thanks again.................more?
Wait....110's better in the corners!, well, I'm all about that !! ( Old but sporty enough !! ).
« Last Edit: May 18, 2009, 05:30:02 PM by Spanner 1 »
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Offline Gordon

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I have a 100 on the rear of my K1.  I've never had any other size on it so I don't have any comparison, but this size has worked great for me.  Good wear across the width of the tire, not just along the middle. 

Offline Spanner 1

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Gordon, I know it's a 'fashion' issue, but does a 100 rear look really 'anemic' on a K.., viewed from the back ?
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Offline Gordon

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Gordon, I know it's a 'fashion' issue, but does a 100 rear look really 'anemic' on a K.., viewed from the back ?


I don't think so, but then it's all I've ever seen on this bike, so it's what I'm used to.



Offline MCRider

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If a 4.00 was stock that equates to 1.01 metric. So a 100 is just an unnoticable skosh smaller.

A 110 metric would be 4.33 inches, so slightly wider, but not as wide as a 4.50 which we used to run all the time pre-metric. A 120 would be 4.72in which is wider than the 4.50 we used to run, so just a skosh too wide for the rim.  Just FYI.
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Offline Spanner 1

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Thanks G and MC......nice pic, G.
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Offline Scrubs

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I run a 130 tyre on a 3" rim - no clearance issues.

Offline 333

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My K4 had a 130 on it when I bought it.  When going into a turn, it "fell" off of the center of the tire into a turn, and I had to work to keep it from falling into a tighter turn than I wanted.
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Offline MCRider

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My K4 had a 130 on it when I bought it.  When going into a turn, it "fell" off of the center of the tire into a turn, and I had to work to keep it from falling into a tighter turn than I wanted.

That would show the difference in the rims, assuming yours was stock, that's how a too wide tire would perform.

A 130 on a 3" rim as scrubs has would feel really good.
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Offline GammaFlat

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Gordon,

Where might your baffles be?

:)
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Offline anthony

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Re: 130/90/18 or 120/90/18 new rear tire on my K1, which ?, any opinions ?
« Reply #20 on: March 28, 2011, 08:09:51 AM »
i am thinking of putting a 130 on a stock rim. has any one tried this yet

Offline MCRider

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Re: 130/90/18 or 120/90/18 new rear tire on my K1, which ?, any opinions ?
« Reply #21 on: March 28, 2011, 08:14:03 AM »
i am thinking of putting a 130 on a stock rim. has any one tried this yet
Read "333"'s post above. A 130 on a stock rim (2.15x18) is too wide. The bead won't seat safely and the ride is as 333 describes.

If your bike is later with the 2.5x17 rims, the 130 is OK.
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1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
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Offline anthony

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Re: 130/90/18 or 120/90/18 new rear tire on my K1, which ?, any opinions ?
« Reply #22 on: March 28, 2011, 08:53:59 AM »
ok thanks a wreaking yard near me has new cash and carry tires for $20 it is a 130 80 18 my bike has a 18 1.85

Offline MCRider

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Re: 130/90/18 or 120/90/18 new rear tire on my K1, which ?, any opinions ?
« Reply #23 on: March 28, 2011, 08:57:31 AM »
ok thanks a wreaking yard near me has new cash and carry tires for $20 it is a 130 80 18 my bike has a 18 1.85
Must be a 500/550? 130 is way too big. I was speaking of CB750.
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1988 NT650 HawkGT;  1978 CB400 Hawk;  1975 CB750F -Free Bird; 1968 CB77 Super Hawk -Ticker;  Phaedrus 1972 CB750K2- Build Thread
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Offline anthony

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Re: 130/90/18 or 120/90/18 new rear tire on my K1, which ?, any opinions ?
« Reply #24 on: March 28, 2011, 11:36:45 AM »
ok thank you its a 550