Oh! The Pressure
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- Solina Dave
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Oh! The Pressure
I wouldn't doubt that everyone is pretty well sick of this subject, but here it is again anyway!
Tire pressure. I've been riding my GL1000 for 40 years now, and I still don't know what would be the best tire pressure to put in my tires.
The owner's manual, written 40 years ago says,"vehicle capacity load limit 360 lbs." Believe me, mine has all of that. It also says that the front should be 28 psi, and the rear should be 40 psi. The tires I run are rated 41 psi max.
I usually run 32 front and 38 rear, but I'm not sure why. I can see having the 40 psi in the rear tire due to load. But I think I'm running 30, or 32, or 34 psi because someone at one time or another has said, "28 psi, that's too low." How do they know that?
Why is the factory spec. 28 psi, if that's too low? Wouldn't they likely know the best tire pressure. After all they built the bike.
Also, do you think that Honda, if they were to rewrite the GL1000's manual today, would change those factory spec. pressures, based on the fact that tire technology is 40 years improved?
The pressure's getting to me ............................... Dave
Tire pressure. I've been riding my GL1000 for 40 years now, and I still don't know what would be the best tire pressure to put in my tires.
The owner's manual, written 40 years ago says,"vehicle capacity load limit 360 lbs." Believe me, mine has all of that. It also says that the front should be 28 psi, and the rear should be 40 psi. The tires I run are rated 41 psi max.
I usually run 32 front and 38 rear, but I'm not sure why. I can see having the 40 psi in the rear tire due to load. But I think I'm running 30, or 32, or 34 psi because someone at one time or another has said, "28 psi, that's too low." How do they know that?
Why is the factory spec. 28 psi, if that's too low? Wouldn't they likely know the best tire pressure. After all they built the bike.
Also, do you think that Honda, if they were to rewrite the GL1000's manual today, would change those factory spec. pressures, based on the fact that tire technology is 40 years improved?
The pressure's getting to me ............................... Dave
"ASSUME NOTHING"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
- desertrefugee
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Re: Oh! The Pressure
Forget the owner's manual. Inflate according to the tire manufacturer's recommendation. That 28 was for tubed bias ply tires. If you're still running those, then it's probably close, but I'd still run 32'ish.
The problem is that there are lots of conditions that alter the pressure requirement - weather, load, tire type. Best to apply tire manufacture's recommendations based on your riding conditions. I run 40/42 on my Valkyrie running Avon Cobras. 35/35 on the '78 GL with Shinko 230's.
I just did a quick search and found what looks like a pretty good overview by Continental here:
https://www.continental-tires.com/motor ... -tires/faq
The problem is that there are lots of conditions that alter the pressure requirement - weather, load, tire type. Best to apply tire manufacture's recommendations based on your riding conditions. I run 40/42 on my Valkyrie running Avon Cobras. 35/35 on the '78 GL with Shinko 230's.
I just did a quick search and found what looks like a pretty good overview by Continental here:
https://www.continental-tires.com/motor ... -tires/faq
- Life is not about waiting for the storms to pass. It's about learning to ride in the rain.
- Solina Dave
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Re: Oh! The Pressure
Inflate according to tire manufacturers recommendation. Where do you find that? Is that the max. pressure of 41 psi. indicated on the sidewall?desertrefugee wrote:Forget the owner's manual. Inflate according to the tire manufacturer's recommendation. That 28 was for tubed bias ply tires. If you're still running those, then it's probably close, but I'd still run 32'ish.
From the Continental link, under "Advice on tire pressure", they state the following:
We do however advise you always to ride at the highest pressure level given from the motorcycle manufacturer.That's 28 psi on the front for a GL1000. Please note that the maximum load of the tire depends on the inflation pressure. This means that you have to increase the inflation pressure up to the maximum pressure stated on the sidewall of the tire to achieve the maximum load carrying capacity.That's 40 psi. rear on a fully loaded GL1000.
I use, as does almost every GL1000 rider with an unmodified bike, bias ply/tube type tires. You say that you'd still run 32'ish in the front. Why would you run 32 psi., when the bike manufacturer, and the Continental Tire advisor, says to run 28 psi.?
"ASSUME NOTHING"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
- desertrefugee
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Re: Oh! The Pressure
I don't run Contis. I run Shinkos on my 1000. I used that link as an example of the wealth of literature available for those who poke around.
GL1000's are around 40 years old, and tires and tire technology were far different when Honda made those recommendations - when Gerry Ford was president. The pressures recommended by Honda will, in most cases, no longer apply. Tire technology has drastically improved in the last four decades.
I still maintain that the best bet is to check with the tire manufacturer for their recommended pressures. Sidewall numbers are not recommendations - they're maximum pressures. The Shinko 230 has a maximum rating of 41 pounds on the sidewall. I think I'm OK at 32. I don't think Soichiro Honda would mind if I fudged on their 40 year old spec.
...besides, the tires last A LOT longer with higher pressure.
GL1000's are around 40 years old, and tires and tire technology were far different when Honda made those recommendations - when Gerry Ford was president. The pressures recommended by Honda will, in most cases, no longer apply. Tire technology has drastically improved in the last four decades.
I still maintain that the best bet is to check with the tire manufacturer for their recommended pressures. Sidewall numbers are not recommendations - they're maximum pressures. The Shinko 230 has a maximum rating of 41 pounds on the sidewall. I think I'm OK at 32. I don't think Soichiro Honda would mind if I fudged on their 40 year old spec.
...besides, the tires last A LOT longer with higher pressure.
- Life is not about waiting for the storms to pass. It's about learning to ride in the rain.
- Rednaxs60
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Re: Oh! The Pressure
Tire pressure will also affect tire longevity. I have Michelin II on my '85 LTD - have 40/40 front/rear. Ride is just fine. I do trips 2 up as well, and no problem either. I would recommend inflating your bike tires to 40 PSI front/rear and ride it at this pressure for a while, adjust as required.
Cheers
Cheers
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1985 GL1200 Limited Edition
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Ernest
1985 GL1200 Limited Edition
2014 Can-Am Spyder RT LE
2021 Royal Enfield Himalayan
1995 GL1500 SE CDN Edition (sold)
2012 Suzuki DL1000 VStrom (sold)
Ontario 1985 GL1200 Limited Edition (sold)
2008 GL1800 (sold)
- Sagebrush
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Re: Oh! The Pressure
I replaced the stock rear tire a R60 with the same sized tire but a R70 on my Gl1800 Goldwing. This tire is stock for a Valkyrie. The slightly taller sidewall did a number of things, all positive, for the bike. However, I found regardless of recommended tire pressure I could not get any longevity at any tire pressure below 50psi. I ran 50psi in the rear through numerous tire replacements and different brands of tires over the years and never had a single problem. Only when I lowered the pressure did I run into premature cupping and excessive wear. Handling was always excellent at 50psi. You should not shackle your thinking to a manual and experiment a little to find the ideal pressure for your particular bike and riding style. In my experience over pressure on a motorcycle tire isn't nearly as harmful as under pressure.
Dean Spalding
Raleigh, NC
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." - Albert Einstein
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Raleigh, NC
"Two things are infinite: the universe and human stupidity; and I'm not sure about the universe." - Albert Einstein
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- Oldewing
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Re: Oh! The Pressure
Yep, I am with Sage on this. Higher than normal pressures are needed for longer life of tires. I too have not noticed any ill effects of higher (48/50) in our back tires, or front's for that matter.
On both my 1000 and 1100's I run 46 front, 48/50 rear. The D4 on the back of my 1800 is over 12K and not half gone.
On both my 1000 and 1100's I run 46 front, 48/50 rear. The D4 on the back of my 1800 is over 12K and not half gone.
82 GL1100 Interstate-Oldewing October 23 BOTM
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Sometimes I wrestle with my inner demons.........
Other times we just hug.......
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- desertrefugee
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Re: Oh! The Pressure
Yep. The last line of my reply above speaks to higher pressure and tire life. I run 40/42 with the Avons on my Valkyrie for just that reason. With the '78 and the Comstars, I will admit I'm a little spooked and I am running tubeless and because of that run lower pressures - more out of paranoia than anything scientific. The Comstar was an early rim and tubeless motorcycle technology was still developing.
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- pierce
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Re: Oh! The Pressure
Unfortunately the experts, and all tire manufactures disagree with anything other than factory manual psi.
I have searched endlessly to find an expert that suggests otherwise, but have come up empty. I also talked with a local mechanic who is a legend in the motorcycle community, and he attributes all the differing opinions to the influx of 'weekend mechanics'.
From am expert on classic motorcycles:
..... I mistakenly believed that because the bikes remained static while tire technology changed, you should follow the tire manufacturer’s recommendations on the sidewall for inflation. A little research has shown me that is not the case. Every tire manufacturer’s website says follow the motorcycle manufacturer’s recommendations for inflation. A few recommend staying at the top of the recommended inflation range. There are a couple of sites that recommend a change for high-speed, two up, fully-loaded touring. Inflate the front tire to the motorcycle manufacturer’s recommended tire pressure, and the rear to the tire manufacturer’s maximum pressure. The reason given for the front pressure is that is how the braking performance was tested when the bike was made, and will result in the best braking.
MChttp://www.motorcycleclassics.com/tech-corner/ ... 0z14mjzbea
And I'm positive this won't change your mind.
I have searched endlessly to find an expert that suggests otherwise, but have come up empty. I also talked with a local mechanic who is a legend in the motorcycle community, and he attributes all the differing opinions to the influx of 'weekend mechanics'.
From am expert on classic motorcycles:
..... I mistakenly believed that because the bikes remained static while tire technology changed, you should follow the tire manufacturer’s recommendations on the sidewall for inflation. A little research has shown me that is not the case. Every tire manufacturer’s website says follow the motorcycle manufacturer’s recommendations for inflation. A few recommend staying at the top of the recommended inflation range. There are a couple of sites that recommend a change for high-speed, two up, fully-loaded touring. Inflate the front tire to the motorcycle manufacturer’s recommended tire pressure, and the rear to the tire manufacturer’s maximum pressure. The reason given for the front pressure is that is how the braking performance was tested when the bike was made, and will result in the best braking.
MChttp://www.motorcycleclassics.com/tech-corner/ ... 0z14mjzbea
And I'm positive this won't change your mind.
1976 GL1000
1978 Gl1000
1978 Gl1000
- desertrefugee
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Re: Oh! The Pressure
Just like an oil topic!
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- Solina Dave
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Re: Oh! The Pressure
By the way, what is the best oil to use!! ..........Just kiddin'!!.........I think you're absolutely right. "Just like an oil topic!"desertrefugee wrote:Just like an oil topic!
Having said that, I think I agree with Pierce and the, "expert on classic motorcycles."
I can see inflating the rear tire to the maximum factory recommendation, as it relates to loading. I the case of a '78 GL that would be 40 psi. The tire I use is rated 41 psi. max. That should also give me improved rear tire mileage.
I agreed that the factory motorcycle design recommendation of 28 psi. in the front tire would be better for braking.
I've always been in the habit of changing both front and rear tires when the rear tire is done. I just felt more comfortable doing it that way, although it did hurt, scrapping a relatively good looking front tire. Maybe if I can improve my rear tire life by maxing out the pressure at 40/41 psi. it won't hurt as much changing both tires.
Also, I see a statement that pressures of 46 to 50 psi. are being used. Is this a different tire than I'm used too? Or is this a substantially greater pressure being applied, over the tire manufacturers maximum recommendation?
Dave
"ASSUME NOTHING"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
- Solina Dave
- Titanium Member
- Posts: 306
- Joined: Sat Sep 19, 2015 2:30 pm
- Location: Port Hope, Ontario
Re: Oh! The Pressure
Just to add a little bit of information, and to possibly confirm what some of you are saying, I contacted Shinko and received the following information.
My question was:
"I have a 1978 Honda GL1000. Maximum factory load recommendation is 360 lbs. That's very close to the current loading. The 40 year old owners manual suggests 28 psi. front and 40 psi. rear. I'm considering the Shinko 230 Tour Master tires. I'm not an aggressive rider, but I do travel longer distances at times. What tire pressure would you recommend for these tires, to optimize handling and generate better tire life. I read a review from 6 years ago that claimed to have noticed a compromised level of tire wear, possibly due to a softer compound rubber being used, to better enhance ahhesion to the road. Any advice, especially regarding tire pressure would be welcome."
Shinko's reply was:
"Shinko recommends running the max psi on the sidewall whenever possible and never more than 5 psi below for rider comfort. This helps reduce heat buildup and increases tread life."
..........Dave
My question was:
"I have a 1978 Honda GL1000. Maximum factory load recommendation is 360 lbs. That's very close to the current loading. The 40 year old owners manual suggests 28 psi. front and 40 psi. rear. I'm considering the Shinko 230 Tour Master tires. I'm not an aggressive rider, but I do travel longer distances at times. What tire pressure would you recommend for these tires, to optimize handling and generate better tire life. I read a review from 6 years ago that claimed to have noticed a compromised level of tire wear, possibly due to a softer compound rubber being used, to better enhance ahhesion to the road. Any advice, especially regarding tire pressure would be welcome."
Shinko's reply was:
"Shinko recommends running the max psi on the sidewall whenever possible and never more than 5 psi below for rider comfort. This helps reduce heat buildup and increases tread life."
..........Dave
"ASSUME NOTHING"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
- desertrefugee
- SUPER BIKER!!!!
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Re: Oh! The Pressure
Exactly what was discussed earlier in this thread! I've got almost 16k miles on a set of Avon Cobras on the Valk and they look like they could go another 16. I run them at 40/42.
- Life is not about waiting for the storms to pass. It's about learning to ride in the rain.
- John Schmidt
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Re: Oh! The Pressure
Generally the higher pressures are good for tread life. Watch how your tires are wearing, if it seems fairly even across the tread you've pretty much hit the "sweet" spot. If increased wear in the center then it's probably a bit over inflated, and by the same token if wearing more to the outside....under inflated. Myself, I run 40 in the front tire on my Valkyrie bias ply Metz, and 36-38(depending on load) in my 195/60-16 rear car tire. I changed the front tire out at 17k due to age only, still plenty of tread. As for the rear car tire....I have no idea yet what the final mileage will be. The last one I changed at 27k due to age with a load of tread left.
Now, let me tell about my oil....it's really slippery!
Now, let me tell about my oil....it's really slippery!
1984 GL1200 Standard, work in progress
1998 Valkyrie Tourer, my Honda Davidson
1998 Valkyrie Tourer, my Honda Davidson
- Solina Dave
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Re: Oh! The Pressure
What's your opinion regarding the following statement?
"Every tire manufacturer’s website says follow the motorcycle manufacturer’s recommendations for inflation. A few recommend staying at the top of the recommended inflation range. There are a couple of sites that recommend a change for high-speed, two up, fully-loaded touring. Inflate the front tire to the motorcycle manufacturer’s recommended tire pressure, and the rear to the tire manufacturer’s maximum pressure. The reason given for the front pressure is that is how the braking performance was tested when the bike was made, and will result in the best braking."
Thanks...... ...Dave
"Every tire manufacturer’s website says follow the motorcycle manufacturer’s recommendations for inflation. A few recommend staying at the top of the recommended inflation range. There are a couple of sites that recommend a change for high-speed, two up, fully-loaded touring. Inflate the front tire to the motorcycle manufacturer’s recommended tire pressure, and the rear to the tire manufacturer’s maximum pressure. The reason given for the front pressure is that is how the braking performance was tested when the bike was made, and will result in the best braking."
Thanks...... ...Dave
"ASSUME NOTHING"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
1st motorcycle-1977 Honda CB550F Super Sport
2nd motorcycle-1978 GL1000
"Not riding a motorcycle is wrong"
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