Author Topic: what tire pressure do you run ?  (Read 24577 times)

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Offline Serge

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what tire pressure do you run ?
« on: September 14, 2006, 09:57:44 PM »
I was told in a dealership yesterday that I gotta run 40 psi on my new BT45, if I want them to last, not 30 as was recommended in 1978.  But this will make a contact patch smaller .. from other side it should  improve gas mileage..  The cheap front dunlop I bought on e-bay 5000 miles ago and run at 28-30 psi has almost no thread left by now...   what pressure do you run?
if it ain't broken it does not have enough features yet..

Offline seaweb11

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Re: what tire pressure do you run ?
« Reply #1 on: September 14, 2006, 10:21:34 PM »
On the street 40lbs

Off road rock climbing 15lbs.

Offline DammitDan

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Re: what tire pressure do you run ?
« Reply #2 on: September 14, 2006, 11:22:37 PM »
I run 28 on the front 36 on the back.  1982 CB650 with '79 comstar mag rims and Bridgestone S11 Spitfires front/back.


I've always been curious about this myself, as it says 40psi on the tire itself, and 28/36 in the clymer manual.
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Offline mcpuffett

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Re: what tire pressure do you run ?
« Reply #3 on: September 15, 2006, 02:41:00 AM »
28 psi front, 30 psi rear , dunlop TT 100's  ;),     mick.
Honda CB750 KO 1970,   Honda VTX 1300 2006, Lancaster England.

Offline MikeDeB

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Re: what tire pressure do you run ?
« Reply #4 on: September 15, 2006, 02:43:07 AM »
28 psi front, 30 psi rear , dunlop TT 100's  ;),     mick.

The same as Mick.
Mike (Old SOHC/4 #2641)
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liaudio

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Re: what tire pressure do you run ?
« Reply #5 on: September 15, 2006, 04:04:19 AM »
Front 100/90/19 BT45's = 30
Rear 130/80/18 = 32

If you ride w/ a passenger, bump it up a few psi

Offline dusterdude

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Re: what tire pressure do you run ?
« Reply #6 on: September 15, 2006, 05:42:29 AM »
doesnt the side of the tire have a recommended pressure setting?
mark
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Offline BobbyR

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Re: what tire pressure do you run ?
« Reply #7 on: September 15, 2006, 07:05:28 AM »
I don;t go as high as 40 on my Battleaxes, but the old recommended pressures are no longer valid with these newer style tires. I find they really make the bike feel sloppy. Last week I found myself stuck on a dirt road. When I got off to see if i had any pebbles stuck in the tread, I could clearly see the contact patch and it was 100%. at 35lbs. I may bump up to 40lbs to see if I get better response.
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Offline DrMark

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Re: what tire pressure do you run ?
« Reply #8 on: September 15, 2006, 07:31:11 AM »
That is a good question. Which is most correct? The Honda specs or the tire manufacturer specs. Does running your tires at Honda tire (lower) pressure specs void the warranty from the manufacturer? What are your thoughts?
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Offline Jugghead

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Re: what tire pressure do you run ?
« Reply #9 on: September 15, 2006, 08:49:19 AM »
Hmmm.  Good post!
I run my (new last fall) Cheng Shin original tread patterns (on a CB350F) at the inflation specs listed on my back fender:
26psi up front, and on the rear, about 28psi (solo), and up to 32psi over 200lbs (two up).
Should I switch over to the PSI recommendations listed on the tires' sidewalls?
Am I right in assuming higher tire pressures reduce tread contact with the road surface?
What is this advantage?
Do harder tires (higher PSI) corner better?
Do they offer less traction due to less surface area in contact with the road?
i would hate to over-inflate and wind up dishing the bike in a corner.
« Last Edit: September 15, 2006, 09:08:51 AM by Jugghead »
9/72 CB350F...15k miles and rising

Offline nickjtc

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Re: what tire pressure do you run ?
« Reply #10 on: September 15, 2006, 09:46:05 AM »
28 front, 40 rear, if loaded. I always use the pressures recommended by the bike manufacturer. The pressures on the tyre are maximums, since the tyre manufacturer does not know where the tyre will end up.

If you deviate from the recommended pressures you will have potential problems:

Too low: excess heat build up in the tyre which in extreme cases could be catastrophic. Worst offenders are Gold Wing and other 'dresser' riders who cannot easily get at the tyre valve to check pressures.

Too high: un-necessarily harsh ride with a reduced contact patch which might be dangerous in inclement weather.

How to check if your pressures are right: measure them with the tyres cold. Go for a long-ish ride (enough to get the tyres up to temperature) and measure the pressures again. The difference should be no more than 10%.
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Offline ofreen

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Re: what tire pressure do you run ?
« Reply #11 on: September 15, 2006, 09:53:09 AM »
On my 750, I run 38psi in the front Metezler Lazertec, 40psi in the back ME88.  With those pressures, handling is good and traction is good enough that you can easily drag hard parts on each side.  Any less pressure than that, the tires squirm too much.  I've been using these tires for many years now on the 750, and get around 15,000 out of the front, and 12,000+ on the rear
Greg
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Offline kzoorue

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Re: what tire pressure do you run ?
« Reply #12 on: May 11, 2007, 09:50:39 AM »
With my new tires (CB 750) started out with 40 psi for both but front tire was pretty bouncy at mid speeds. On the highway didn't notice. I would suggest (as inferred before) to replace tires with original specs and go by recommended pressure for the bike. I now go 28 front and 35 rear. You ought to be able to find your specific bike on this site.


Offline TwoTired

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Re: what tire pressure do you run ?
« Reply #13 on: May 11, 2007, 10:32:01 AM »
Absolute tire pressures are meaningless without noting proper tire to rim size fitments.  If you are running stock sizes on stock rims, the Honda recommendations are appropriate.  I run pressures mid point between two and one rider specifications, so I am somewhat prepared to take a passenger when need arises.  (Full pressures when air compressor is available)  Plus, I am heavier than the "standard weight" Honda rider and carry saddle bags (some of my bikes also have added fairing weight.

Oversize tires don't fit properly on undersize rim widths.  Such fitments will require higher pressures than Honda recommendations to bolster sidewall rigidity.  The amount of pressure increase will have to be found by experimentation and will vary with the amount of size mismatch.

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Offline Jinxracing

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Re: what tire pressure do you run ?
« Reply #14 on: May 11, 2007, 11:35:50 AM »
How to check if your pressures are right: measure them with the tyres cold. Go for a long-ish ride (enough to get the tyres up to temperature) and measure the pressures again. The difference should be no more than 10%.

I was going to recommend using an infrared laser-thermometer like the F1 teams use (about $35), but I like your idea even better!
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bobsmith

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Re: what tire pressure do you run ?
« Reply #15 on: May 26, 2007, 07:37:32 AM »
Mine is mostly all highway riding with a few twisties for fun, and i run my Cheng Shins (OK, I'm a tightwad) at 35/40 without any problems.. I get 10,000 rear, and my front will make it to 20,00 easy.

Offline merc2dogs

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Re: what tire pressure do you run ?
« Reply #16 on: May 26, 2007, 10:13:38 AM »
 I aalways adjust pressure to planned riding, and generally stay somewhere between bike recommended and tire max pressures.
 at the honda recommended pressure the bike feels squirmy to me, and when cornering at speed it feels as though it understeers from tire walk

 at tire max it feels a bit too stiff, though cornering more closely follows the mental 'map', though with a bit of oversteer, and road surface texture can be felt as a low almost subliminal vibration, so I adjust to best overall feel for comfort to get rid of the vibration, without straying too far from my mental map when cornering. 

 If going on long cruises with comfort more in mind, I'll reduce closer to factory specs, if more 'fun' is in mind I edge up towards tire max.

 not much help as to actual pressure run, but it's the way I go.

Ken.