[George Baker]

Greetings,
     Thumbing through my new GT owners manual the other day (it did not come with the bike which I have had for two months now). Anyway, I noticed the recommended front tire pressure is 20psi. Is it just me or does that seem somewhat low. Having set up many many new bikes of different makes over the years I have never seen such a low recommended pressure on any street bike. I have thought something like 28psi would be more in order. Has anyone out there played around with different pressures, if so what did you find?

GB

[ace.cafe]

This has been a subject of great debate since the UCE bikes came out.
The only consensus is that you should inflate to what seems best to you.

[Jellyroll]

Look on the tire sidewall. Use the manufacturers' recommended PSI. Deflate a half pound at a time for more bite/slower steering, inflate a pound at a time for extra weight such as gear, a fine filly or that burrito you shouldn't have eaten

[Arizoni]

The problem with using "the manufacturers recommended PSI" is it is usually the MAX recommended pressure the tire can handle.

It often is much higher than the pressure the motorcycle manufacturer recommends and it almost never is the pressure that gives the best ride or control.

The Royal Enfields were designed in an age where a 20 psi front and 24 psi rear tire pressure was common, even for bikes like the Triumph and BSA (and Royal Enfield) 650 + cc twins.

I suggest sticking with Royal Enfields recommendation until it proves to be a problem.
Engineers don't just pick a number out of the air before making a tire pressure recommendation.  There is always a lot of hours of test riding involved.

[motorman2whel]

"the tire manufacturers PSI on the sidewall of the tire" is the MAX recommended pressure the tire can handle. 

[AgentX]

Engineers don't just pick a number out of the air before making a tire pressure recommendation.  There is always a lot of hours of test riding involved.

Even if they did make a rational and/or road-tested choice, it's likely based on Indian conditions...40-50mph over questionable roads.

[JohnDL]

The same discussion is going on on Hitchcocks forum:

http://www.hitchcocksmotorcycles.com/viewforum?currentpageref=&function=viewthread&forumref=14427&threadref=14427&currentforumpage=&currentforumorder=

20psi does seem low, but all the tyre manufactures say to follow the owners handbook tyre pressure recommendations.

John

[cafegtgirl]

I will not get into a pissing match, but being a certified Honda tech for over 35 years and professionally working on RE's for over three years, listen to what the manufacturers say about tire pressure. They design the bikes and understand the loading and handling characteristics better than the public. You can run any pressure you desire for whatever reason, but don't complain about handling or wear issues and then blame it on a poorly designed bike.
Buell(EBR) had the right idea a few years back. Being a small company with a limited number of models, they were able to check most all sport tire offerings on their bikes and found the best overall tire to run. I switched to their suggestion, and pressure settings, and have gotten excellent performance and wear.

[gashousegorilla]

I will not get into a pissing match, but being a certified Honda tech for over 35 years and professionally working on RE's for over three years, listen to what the manufacturers say about tire pressure. They design the bikes and understand the loading and handling characteristics better than the public. You can run any pressure you desire for whatever reason, but don't complain about handling or wear issues and then blame it on a poorly designed bike.
Buell(EBR) had the right idea a few years back. Being a small company with a limited number of models, they were able to check most all sport tire offerings on their bikes and found the best overall tire to run. I switched to their suggestion, and pressure settings, and have gotten excellent performance and wear.

   +1

  Take the C-5 for example with the Avon Roadriders.   Very stiff side walls and very round profile.  The 18 to 20 front and 24 to 28 works fine, and has been used for many years on these bike.  That lower front pressure, also gets the riders weight more forward, which also tends to have stabilizing effect on the frame.   If you run higher pressures with these tires , with the same rider it tends to have the opposite effect..... especially with the earlier C-5's.

  The same rider on the same bike, installing BT 45's , found those low pressures NO good. A lot of wheel hop and a lot of bounce in the front end.  He wound up in the area of 30 front and 34 rear. And the bike performed like the Roadriders that had the lower pressures.  Different tire with a different make up  and side wall....I guess.   So Yeah, I think the engineers DO test things with the brand, size and model tire that comes on the bike stock.  Because they can't know or test all possible options out there on the market.



 

[John Flatt]

My R/E owners manual say front 32psi rear 36psi