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Discussion Starter #1
well, got thru a little early today. So I mounted up the kumho runflat and put it on.

Took the 30 mile 45 minute ride home cautiously at first.

1st observation was it felt squarrelly going over the shower type drains in the building. No big deal.

Once on the street though I never felt my bike so smooth. And quiet. I did feel some lane transistions where road upgrades were done. In the metroplex they fix one lane at a time to keep road rage and vehicles manslaughter rates down. So one lane to the next felt "funny".

It didn't take long til I was lookin for them to see if I still felt it.

Honestly I didn't feel like I had to counter steer more or anything. My high speed and low speed turns were so smooth.

Definitely got some of my confidence back on riding a bike in just a few short miles. For those of u who don't know I went down on my vtx 1800t and totaled it so been a little gun shy to say the least.

As far as nitrogen, here's where I started but will reduce pressure and keep track on what happens.

Air temp 94' street temp 108' at shop.

Started with 39 psi.

At home wheel temp at sensor 159' at sidewall 145 and tread 138.

Air pressure went to 42 psi so 3 psi increase.

I will take it down to 37 tomorrow and see what the ride does. Would like it to top out about 40 psi for wear purposes.

Thanks for all you guys help. It's amazing we have 5 wing riders in our department and they freaked when I laid my new bike on its side to change the tire. Of course most was in disbeLief that I would put a ct on.

Dw
 

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Congrats on your new tire!:thumbup: Welcome to the darkside!
 

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37psi is way too much for that runflat. The center will wear out real quick. Low 30s or even lower will work far better.
 

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As said, 30-34 is the norm without excessive wear in the middle on a RF. I like 32 psi.
 

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:congrats: racer!:thumbup::thumbup::thumbup: The more you ride it, the more you will love it!:thumbup::thumbup::thumbup:
 

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Discussion Starter #7
thanks guys,

also remember i asked the guys who have this tire and an aftermarket monitoring system what their increase of pressure was when the tire got hot. most said 5 - 6 psi, only one gave an ambient temp range of mid 70's and rob said 10 to 20%. which 20% of 32-34 psi is 6 - 7 psi.... so thats 38 - 41 psi hot.

i'm running nitrogen and only seen a 3 psi increase about 8% roughly... at 93' ambient temp. so roughly people are seeing, from what people replied, about 38 psi to 41 at temp. so my 37 psi start and maybe 40 psi hot is very close and keeps my tpws light off. plus you put my fat butt on there and now does 1 - 2 psi matter? maybe....

having said all that, i will still monitor tire pressure for a couple of weeks and see what happens. keep a chart and make the decision on what to do pressure wise.

any more input from those running a tpms and can give me ideas at what PRESSURES they cruise at, 45 minute runs etc would be good info....

thanks again guys, this is fun. first time i have been interested in anything automotive/bike related in years....

dw:thumbup:

my disclaimer: would i ever pay for nitrogen, hell no. but its free to me and the pressures changes are minimal, pressure loss over time is less, so its convenient for me today and what i'm doing on my bike!! YMMV
 

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Welcome to the Darkside! I run the Pirelli ROF, but I found that with higher pressures the bike seemed to wander a lot. The magic number for me is 33psi for both front and rear (cold, plus it's easy to remember). G709 is my shoe up front. Play around with your pressures...a pound or two can make a surprising difference in the handling and wear. 8k on my BMT and only 1/32" difference across the tread so far and the Wing handles and rides like a dream :yes1:
 

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DW, sorry I have been so busy to get with you about the ride I will get there sometime and show you the dunlop 175/60/16 rf that i run that you can run at 40 psi and keep the tpms ligh off wears fine you tell me what you think sinse it has about 10k on it now.
 

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Discussion Starter #11
DW, sorry I have been so busy to get with you about the ride I will get there sometime and show you the dunlop 175/60/16 rf that i run that you can run at 40 psi and keep the tpms ligh off wears fine you tell me what you think sinse it has about 10k on it now.
That's fine. Give me a buzz and we will go for a ride.

Dw.
 

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You're on your way. When riding 1 up, with mild temps (70s) I only see about 10% max increase. For example last weekend, I started out at 28 and only say an increase to 32psi. Outside temps were 75F and I was 1 up riding at 45-55 mph.

Weight makes a big difference. One up, I probably have about 210lbs of additional load on the bike (135lbs of rider fully geared up, ~50lbs of accessories [highway pegs, fog lamps, spoiler, etc], and ~25lbs of "gear" in the trunk/saddlebags). With that configuration I see ~10%. Nearly identical to the heat gain in the front tire.

If I ride two up fully loaded then I'm looking at about 450lbs of riders, accessories, and gear. I'll see 20%+ increase in pressures in that configuration especially in hot temps (upper 90s). I never see 20% increases unless I'm heavily loaded for long distance riding.

For me, 34-36psi is what I'm shooting for 1 up for even tire wear and around 36-38 for two-up (I increase to 30-32psi cold for heavily loaded 2 up riding). 40psi is likely to give you premature center wear. If you want max wear, I'd suggest targeting a bit lower. I'm guessing somewhere between 36 and 38 hot.

That's just based on my observations. I saw faster center wear on my last tire (Pirelli [email protected]) and I was seeing 40psi+ hot (36psi cold) when fully loaded (~450lbs of weight).

Hope this helps you target your initial operating psi. It's just a SWAG anyway. You'll just have to check the wear after about 5-7k to see the results and adjust accordingly.

thanks guys,

also remember i asked the guys who have this tire and an aftermarket monitoring system what their increase of pressure was when the tire got hot. most said 5 - 6 psi, only one gave an ambient temp range of mid 70's and rob said 10 to 20%. which 20% of 32-34 psi is 6 - 7 psi.... so thats 38 - 41 psi hot.

i'm running nitrogen and only seen a 3 psi increase about 8% roughly... at 93' ambient temp. so roughly people are seeing, from what people replied, about 38 psi to 41 at temp. so my 37 psi start and maybe 40 psi hot is very close and keeps my tpws light off. plus you put my fat butt on there and now does 1 - 2 psi matter? maybe....

having said all that, i will still monitor tire pressure for a couple of weeks and see what happens. keep a chart and make the decision on what to do pressure wise.

any more input from those running a tpms and can give me ideas at what PRESSURES they cruise at, 45 minute runs etc would be good info....

thanks again guys, this is fun. first time i have been interested in anything automotive/bike related in years....

dw:thumbup:

my disclaimer: would i ever pay for nitrogen, hell no. but its free to me and the pressures changes are minimal, pressure loss over time is less, so its convenient for me today and what i'm doing on my bike!! YMMV
 

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ddub, I don't live far from you and 34PSI was a great number for me. I liked it there because I didn't get the sensation of the tire "rolling up" on me. I rarely got over 38PSI when running in the summer.
You can justify yourself using nitrogen and ambient air temp but it is mostly fluff. Even at 34 the the center will wear out first. Not by a lot, and I would run one again in a skinny minute if my new fist choice wasn't available.

It is your "seat of the pants" and the majical number you come up with is really yours and not for too much debate, but on a RF 38-40 is pretty high, even if it were on a 4 wheeler, that BTW recomend 32-34 PSI in most cases.

:congrats: On the DS
 

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Discussion Starter #17
You're on your way. When riding 1 up, with mild temps (70s) I only see about 10% max increase. For example last weekend, I started out at 28 and only say an increase to 32psi. Outside temps were 75F and I was 1 up riding at 45-55 mph.

Weight makes a big difference. One up, I probably have about 210lbs of additional load on the bike (135lbs of rider fully geared up, ~50lbs of accessories [highway pegs, fog lamps, spoiler, etc], and ~25lbs of "gear" in the trunk/saddlebags). With that configuration I see ~10%. Nearly identical to the heat gain in the front tire.

If I ride two up fully loaded then I'm looking at about 450lbs of riders, accessories, and gear. I'll see 20%+ increase in pressures in that configuration especially in hot temps (upper 90s). I never see 20% increases unless I'm heavily loaded for long distance riding.

For me, 34-36psi is what I'm shooting for 1 up for even tire wear and around 36-38 for two-up (I increase to 30-32psi cold for heavily loaded 2 up riding). 40psi is likely to give you premature center wear. If you want max wear, I'd suggest targeting a bit lower. I'm guessing somewhere between 36 and 38 hot.

That's just based on my observations. I saw faster center wear on my last tire (Pirelli [email protected]) and I was seeing 40psi+ hot (36psi cold) when fully loaded (~450lbs of weight).

Hope this helps you target your initial operating psi. It's just a SWAG anyway. You'll just have to check the wear after about 5-7k to see the results and adjust accordingly.
Thanks. Just the info I need.


:congrats: & welcome to the Darkside.
Thanks
Congrats welcome to the dark side
Thanks
ddub, I don't live far from you and 34PSI was a great number for me. I liked it there because I didn't get the sensation of the tire "rolling up" on me. I rarely got over 38PSI when running in the summer.
You can justify yourself using nitrogen and ambient air temp but it is mostly fluff. Even at 34 the the center will wear out first. Not by a lot, and I would run one again in a skinny minute if my new fist choice wasn't available.



It is your "seat of the pants" and the majical number you come up with is really yours and not for too much debate, but on a RF 38-40 is pretty high, even if it were on a 4 wheeler, that BTW recomend 32-34 PSI in most cases.

:congrats: On the DS
Thanks for the input. Nitrogen is like wd40. My buddy swears by it for a fish attractant. We crappie fish a lot. It's made with fish oil he says. I don't know. It works for him but not for me. Maybe cause I'm skeptical. This has got me thinking about testing and documenting both ways but I am sure I would lose interest before I finished and besides, most people don't have access or would not pay to do it anyway. So why waste my time. I use nitrogen daily not because I make money with it, on the contrary it costs me cause the company won't pay for me to fill or refill. But it saves me an hour or better of unproductive time daily cause I don't have to chase low tire light on cars for free.

Dw
 

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Discussion Starter #18
250 miles now

Well I have put 250 miles on the kumho. I love a lot of things about it. The thing I don't like is it feels like the back end is real loose and follows cracks and road imperfections real bad. Scary sometimes. After a farm to market roads ride , then to a 4 lane divided , newly repaved interstate, I ended up on a road under construction. The places where they sand blasted the painted lane markers off frankly scared the hell out of me. I was at the 10-20 mph range and the rear end shifting was bad.

So do I start playing with air pressure? Or is that just the way feel at low speed and u learn to deal with it?

Dw
 

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Ran 32 lbs in mine n center wore bad lowered to 28 n fine just put new wintersport on hopeing to get more than 19,000 on it 1 up ridin most time welcome to ds ride safe
 

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Well I have put 250 miles on the kumho. I love a lot of things about it. The thing I don't like is it feels like the back end is real loose and follows cracks and road imperfections real bad. Scary sometimes. After a farm to market roads ride , then to a 4 lane divided , newly repaved interstate, I ended up on a road under construction. The places where they sand blasted the painted lane markers off frankly scared the hell out of me. I was at the 10-20 mph range and the rear end shifting was bad.

So do I start playing with air pressure? Or is that just the way feel at low speed and u learn to deal with it?

Dw
See how it rides with 32 PSI in it, pressure makes a big difference, you can always add more pressure again if you don't like it.

Even with 0 PSI it will still hold up the bike or a car for that matter so don't be shy about going lower on pressure.

When you are near the sweet spot even a 2 PSI difference changes things.
 
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