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Just bought a new 2009 Vulcan 900 classic lt and checked the tire pressure. Both the front and rear tires had 40 pounds. The maximum for each tire inscribed on the tires is 41 pounds. The Manual said 28 psi front and rear tire. From those of you with experience, what air pressure should be in the tires. Thanks!

lpace502
Tennessee
 

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I just bought a 900 Custom and the manual states 40 psi for the front and 32psi for the rear. This seems backwards, but I have never owned a bike that has the 21 inch front wheel, any suggestions?
 

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The little front wheel has to take the same loads as the bigger classic wheels but with less volume so they have higher pressure. They are softening the ride on the big rear tire but you'll get longer tread life at a higher pressure. Dunlops use 38, Metz 40.
 

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MrClean
Thanks for the input, never thought of it that way about the 21 inch front. But I will do it. As for the back, I have always used around 40 for every bike I `ve ever had.
 

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Did you ever see or watch movies with old WWII and just post war bombers like the B-36 and notice the absolutely HUGE wheels they had? The wheels had to be that big to handle the weight of the bombers which in the case of the B-36 was astronomical. However some bright guy came up with the idea of using Bogey gear configurations which you can see on any large aircraft nowadays. You know the ones with 4 or 6 wheels per landing gear strut. Heck, I think the 747's have 3 or 4 struts in the rear and just the one up front. Landing gear, any gear, are amazing things but they all boil down to the same thing. A given amount of work that needs to be done over a set distance. Amazingly that gets overlooked by even top engineers and you spend hours and hours honing metering pins to let the work be done in the right amount of time without exceeding the force that the structure can safely take. if you're bike hits a bump a 30 mph my 6 inches of rubber has all that travel at a lower pressure to absorb the load. Your 3 inches of rubber has to do the same bit of work so it has to be quite a bit stiffer. I know, beating the dead horse, but thats pretty easy picture now instead of just saying it's got to do the work of a bigger tire.

Or I've just been up to long and it's time for a shower and bed. Either way, them little tires look cool and handle sharp but for long distances, give me the shock absorbing tire.
 

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I have the 900LT as well and Dunlop has told me the following:

"Thank you for taking the time to contact us regarding the proper inflation pressures for the Dunlop D404 motorcycle tires fitted to your Kawasaki VN 900 Vulcan 900 Classic LT. For the original equipment sizes of 130/90-16 front and 180/70-15 rear, we suggest inflating your cold tires to 34 psi front and 38 psi rear for all loads and street conditions. These pressures allow for the tires to deliver maximum mileage before wear out with even tread wear. The lower OEM inflation pressure specs may provide a more comfortable ride, but may result in an irregular wear pattern."
 

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just a ? Why would the manf. tell us to fill to there specs. And most of you say its wrong. Wouldn't you think Kawasaki tested these tires and put these numbers down for a reason?
 

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Your answer, which has been said several times in this thread, lies in the last line of the previous post from Crooksie. Won't retype it on this silly laptop keyboard, please read it there.
 

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I guess I don't understand why you would want to run a different pressure that what the manufacture states with the stock tires.

More pressure means less rubber on the road and that means less traction.

More pressure means you will feel every crack and bump in the road.

More pressure increases the odds of getting a flat

More pressure could make the tire last a little longer maybe but I will take the softer ride any day.

Just my 2 cents worth.
 

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MrClean
Funny you reference aircraft as your example, I am a big avaition nut and have always questioned why so much at the rear of the 747, and not the front. Ever look closely at the C-5 Galaxy?
At any rate, I`ll keep`em up and ride away.
Thanks
 

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When you say rear of a 747 you are actually talking just aft of the rear spar in the carry through area. The aircraft is meant to land with it's nose up and the majority of the load is carried through the mains. After speed is reduced and the impact of landing has been absorbed they bring the nose down. C-5's likewise have a bunch of wheels under the main load of the aircraft and also land primarily on them BUT they are also designed to land with big ol honking tanks and such which when you put the nose down and throw on the thrust reversers throws a bunch of load to the nose of the aircraft. Any less structure on the nose wheel and those forces would have it skidding on the fuselage skins in no time.
 

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all i was asking is this this what you guys think is right or did you talk to kawasaki and this is what there told you what to air up the tires to?
 

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MrClean
I only mentioned "rear" as a referrence, for what is not at the front. I know they`re not tail draggers.
No bob900, I haven`t been in contact with Kawasaki, sometimes the better info can be found here on the forums as we( the customer) do the more real world R&D. But now that you mention it, perhaps an email is in order to ask why the manual and their website list two different pressures.
 
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