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Hi guys just wondered how critical tire pressures are, took the bird out for a quick ride after lots of work found steering heavy when tuning in the drive, felt really heavy on the road and wanting to fall into a roundabout, decided to check the front tire pressure on return was only 7 psi when it should be 42.
 

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consider yourself lucky you didn't crash.

one way i sometimes notice a flat? when i get on the bike, i'm suddenly longer of leg...

get in the habit of at least kicking your tires before a ride. that low of a pressure should be very noticeable. also find out why that pressure was so low. unless you hadn't ridden for a very long time, i'll bet you have a puncture or leaky valve stem.
 

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Hi guys just wondered how critical tire pressures are, took the bird out for a quick ride after lots of work found steering heavy when tuning in the drive, felt really heavy on the road and wanting to fall into a roundabout, decided to check the front tire pressure on return was only 7 psi when it should be 42.
Check your valve centres are tight. You may have a slow leak through the valve. Spray some soapy water on them to double check. I've had it happen after the last true change.
 

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Cougar
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As mentioned by other replies, check for puncture or leaking valve. As for tyre pressures, watch the link attached.
 

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42/42 PERIOD!!!
...also make sure steering head bearings are in good shape...gets tight when problematic. Replaced mine at 135,000 miles...original owner though that doesn’t wheelie (very much) 😂😂
 

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Tyre pressures are very important, especially if you want to stay on your Bird or any two wheels. I always check mine before every ride, check when cold. 42psi F & B as stayed above. Happy riding !!
 

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:ROFLMAO::ROFLMAO:....... not to be disagreeable, but when I used Honda's BS 42/42 I found the thing was horrible in the wet.

I have ridden my BB's (an 02, now an 05) for a total of 18 yrs and 54k + 130K kms with 36psi F and 38R......... so it's not critical unless you are in the 300kph brigade. Also that video above was heading toward this when I pulled out....... setting pressures that suit your climate/weight/style of riding etc etc...... I will return and watch that later......

Keep in mind when the BB was released back in the late 90's the Japs thought they had built the world's fasted land rocket and the tyres specified then are no longer available (what we have now are vastly better). Also, lawyers at Honda probably whispered into the corporate ears, something about legal liability and possible government laws etc.... they were so frightened of being seen as irresponsible manufacturers - now we have road registerable bikes with 200hp in standard trim........

Whenever I see a Honda BB traveling slower than cars in the rain or on damp roads, I know what the rider has set their tyres to..... because they have no feel/grip at 42/42.

I get over 20,000kms out of a set of Michelin PR4's and have pillioned with 40ltr Givi E41 cases and 50Ltr top case (she needed her makeup kit)........ and at max carrying load (I think BB is rated at 400kg..... riders, fuel and luggage). I never needed more than 37psi front and 42psi rear....... day trips without luggage I used 35f and 38r....... but these days on my KTM 1290 SDGT (which is 30kg lighter and 30hp more powerful than my beloved 260kg BB) I use 34F and 36R and still get 15,000kms a set on Road 5's.........

Horses for courses of course...... but for normal law-ish abiding low flying I don't need 42/42...... and the latest gen of tyres are so much better (higher silica dual compounds etc etc) that they just don't need to be set at 1997 tyre era specs.

(y)....... just go ask a m/c tyre fitting/repair shop for practical local advice......
 
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Yep, took a while, but the video man made a good point (as I suspected). So I know from 18years experience on BB's and 184,000kms of multi role riding (fanging the mountains, touring heavy, commuting, all weather long distance travel) that 42/42 is for a particular mindset, not a general recommendation....... try a few pressure ranges and observe how it feels for you in your location. (BTW I've changed a lot of steering head bearings using my cousin's m/c repair-servicing workshop..... and I've never gotten more than 60,000kms/40k miles out of steering head bearings......;)).

But at least you know starting with 36/38 won't cause the world to stop spinning, otherwise I wouldn't be here today ;).

PS The biggest hurdle you will encounter is finding a gauge that is reliable and fairly accurate. I have 3 in my garage and regularly cross check them with my onboard tyre pressure system on the KTM. It's not that critical, but your issue with heavy steering and subsequent discovery of 7psi is a classic case of a dangerous low pressure which could lead to the tyre slipping off the wheel......... any pressure from 32-37psi F and 36-42psi R on the BB would be fine...... it just needs you to test how they feel and choose a setting that you like..... just keep them in the 30's range or you may cause a failure from heat/handling.

Faster/better/track day riders (than me) use much lower 'cold set' pressures because they know the tyre will heat up and increase the pressure by approx +4psi..... and they want grip and feel over mileage...... a long range tourer may want 38/42 cold set due to weight/mileage/economy .......... somewhere in that range is a good pressure for your style.

(y)

PS..... the gauges I have are..... a $15 'PCL' brand pencil/ engraved tube style (made in the UK) - (it is the best), a crappy looking $50 dial gauge style 'Blue Point' (or something) (made in the USA) which is consistent but reads 1 psi high, and a 'Michelin' digital gauge that a well meaning mate gave me as a Xmas gift. The other gauge is a $30k Au KTM in dash gauge :LOL:....... but the main thing is to have something that is consistent and most fuel stations have reliable digital air pumps now...... just remember they show hot pressures as you have ridden to them (usually tyres heat up 2psi for a shortish ride but that varies so much with ambient weather conditions etc, so near enough is good enough unless you are a perfectionist...... but what is perfection?.........
 

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This is why I changed to Steel T-valves and put on an inexpensive TPMS. I know what my tire pressure is getting on the bike and I can see them rise 2 to 4 pounds during the ride. I maintain the 42/42 but I did try the lower pressure in the front. At 36 I was wearing through my PR4 up front to fast so I went back to 42.
The TPMS I got was a $50 set up with a monitor I velcroed to the dash. I had a FOBO set up but didn't like I don't have my phone out to see the pressures all the time. I put it on my daughter's Rebel.

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interesting, xxguy. can you comment on how long the batteries last? have you checked your unit against a known guage for accuracy? got a link to the one you're using?

(y)
 

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:ROFLMAO::ROFLMAO:....... not to be disagreeable, but when I used Honda's BS 42/42 I found the thing was horrible in the wet.

I have ridden my BB's (an 02, now an 05) for a total of 18 yrs and 54k + 130K kms with 36psi F and 38R......... so it's not critical unless you are in the 300kph brigade. Also that video above was heading toward this when I pulled out....... setting pressures that suit your climate/weight/style of riding etc etc...... I will return and watch that later......

Keep in mind when the BB was released back in the late 90's the Japs thought they had built the world's fasted land rocket and the tyres specified then are no longer available (what we have now are vastly better). Also, lawyers at Honda probably whispered into the corporate ears, something about legal liability and possible government laws etc.... they were so frightened of being seen as irresponsible manufacturers - now we have road registerable bikes with 200hp in standard trim........

Whenever I see a Honda BB traveling slower than cars in the rain or on damp roads, I know what the rider has set their tyres to..... because they have no feel/grip at 42/42.

I get over 20,000kms out of a set of Michelin PR4's and have pillioned with 40ltr Givi E41 cases and 50Ltr top case (she needed her makeup kit)........ and at max carrying load (I think BB is rated at 400kg..... riders, fuel and luggage). I never needed more than 37psi front and 42psi rear....... day trips without luggage I used 35f and 38r....... but these days on my KTM 1290 SDGT (which is 30kg lighter and 30hp more powerful than my beloved 260kg BB) I use 34F and 36R and still get 15,000kms a set on Road 5's.........

Horses for courses of course...... but for normal law-ish abiding low flying I don't need 42/42...... and the latest gen of tyres are so much better (higher silica dual compounds etc etc) that they just don't need to be set at 1997 tyre era specs.

(y)....... just go ask a m/c tyre fitting/repair shop for practical local advice......
What a brave post Aussie Dave.
I have found that 42 psi is just too firm for me. I agree that it is optimum but disagree that it's critical. I'm wondering if funwithbono could justify his statement about 42/42 "period".
I'm not experienced with BB, I've only had mine for 5 months but last week I was out on my daily ride and had one of the best rides I've ever had on this bike. I felt really in sync with the machine and confident through corners. It turns-out my tyres were under inflated. Not by much, only 2psi (i.e., down from 42) but that drop in pressure seemed to settle the bike into the road surfaces with the result being a more confident rider. I'm sure you get where I'm going with this so I just want to say that 42 is probably optimum, especially if you are track racing, for example, but it's not optimum for all the varitions that come into play in everyday riding. Just think about the state of Tasmanian back country roads. We have pitted rough surfaces on cornners and I have been scared shitless careering around these corners with tyres inflated to 42 psi. I just don't ride confidently at this inflation so I'm not at one with the bike, which in my mind is critical, period, no offence.
When, I fly into one of these corners I get bucked and kicked around on my seat. That's crazy on a motorbike on a bend. That's the opposite of safe. And I keep hearing 42/42 like it's an unbreakable rule. I'm feeling like a risk taker when I want to deflate my own tyres a bit evn when I know they are too tight for Tassie road surfaces.
What I am saying is that my inexperiece is useful. Because I'm new and have riden the BB at 42psi, I can descibe, with fresh eyes, my experience of this bike's handling, on these roads. Too me, it feels tight springy, flicky and kinda awesome in a start line on a warm day. That same pressure around dodgy corners is then terrifying as the flickiness doesn't soak up the bumps. You then loose your line/flow as you get jerked around in the seat. Drop the pressure a bit on these roads and corners are smoother resulting in a confidence in the bike which is important.
So for me, it's more about find a tyre pressure that impoves handling more than anything else. Do others agree?
 

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I’d second what AussieDave and Nato said above. Road surfaces in India are even more uneven, and we probably don’t carry the kind of speeds you guys do, and I’d easily echo what they said. I’ve typically run 38-38 and found it to strike just the right kind of balance.
Having said that, I’m surprised that the original poster here did not notice the drop in pressure much before it hit 7 psi. Glad you got home safe.
 

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Friend of mine tracks with 36 rear 38 front. Stated that once the tire gets to temp you don't want to be above the factory max. I've run both the above and the 42/42 and can't say I have really noticed a difference at either setting. When I tracked my bird I did run the 37/38 though and it never got really loose. It did drift on 3 occasions but it was very controlled. To the point or lifting the front wheel on the last pass.
 

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What a brave post Aussie Dave.
I have found that 42 psi is just too firm for me. I agree that it is optimum but disagree that it's critical. I'm wondering if funwithbono could justify his statement about 42/42 "period".
I'm not experienced with BB, I've only had mine for 5 months but last week I was out on my daily ride and had one of the best rides I've ever had on this bike. I felt really in sync with the machine and confident through corners. It turns-out my tyres were under inflated. Not by much, only 2psi (i.e., down from 42) but that drop in pressure seemed to settle the bike into the road surfaces with the result being a more confident rider. I'm sure you get where I'm going with this so I just want to say that 42 is probably optimum, especially if you are track racing, for example, but it's not optimum for all the varitions that come into play in everyday riding. Just think about the state of Tasmanian back country roads. We have pitted rough surfaces on cornners and I have been scared shitless careering around these corners with tyres inflated to 42 psi. I just don't ride confidently at this inflation so I'm not at one with the bike, which in my mind is critical, period, no offence.
When, I fly into one of these corners I get bucked and kicked around on my seat. That's crazy on a motorbike on a bend. That's the opposite of safe. And I keep hearing 42/42 like it's an unbreakable rule. I'm feeling like a risk taker when I want to deflate my own tyres a bit evn when I know they are too tight for Tassie road surfaces.
What I am saying is that my inexperiece is useful. Because I'm new and have riden the BB at 42psi, I can descibe, with fresh eyes, my experience of this bike's handling, on these roads. Too me, it feels tight springy, flicky and kinda awesome in a start line on a warm day. That same pressure around dodgy corners is then terrifying as the flickiness doesn't soak up the bumps. You then loose your line/flow as you get jerked around in the seat. Drop the pressure a bit on these roads and corners are smoother resulting in a confidence in the bike which is important.
So for me, it's more about find a tyre pressure that impoves handling more than anything else. Do others agree?
sounds like your rebound is too fast
 

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Horses for courses I guess and I guess its down to riders weight, total load weight and make of tyres but for me I am 100% in the 42/42 camp.
 

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sounds like your rebound is too fast
Are you talking about adjusting the rebound damping dial from hard to soft at the bottom of the rear shock? If so, I have already done this.
I would love to thrown the rear shock over the fence but can't afford anything flashy yet. When I do upgrade the suspension, it will be interesting to see if the deflation of tyres is still neccesary.
 

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Actually does someone want to weigh on rebound damping. It doesn't make sense to me. In my owners manual it says this:
To reduce (SOFT):
Turn the adjuster counterclockwise toward SOFT for a light load and smooth road condition.
To increase (HARD):
Turn the adjuster clockwise toward HARD for a firmer ride and rough road conditions.
So here's my question, shouldn't I be turning the adjuster to soft because of rough road conditions? Why would you want it turned to hard when on rough roads. My sense is that's what's throwing my around in the seat. Hard rebound and tight tyres. So please enlighten me! On rough Tassie roads, turn the dial towards soft or hard?
 

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Nato you want the shock to rebound as quickly as possible without bouncing. That way the wheel can react to road variations as quickly as possible IE dips and holes. Unfortunately the rear shock on the BB has only one adjuster. So what you do to one side effects the other. Here is a tip I was given for rebound. Compress the rear suspension as far as your able. Then release it and watch it's reaction. What your looking for is a slight amount of overshoot. Turn the adjuster to a softer setting. It can be a bit hard to detect, your looking for a bit of bounce. Once you see this turn the adjustment back the other direction until it stops. That should be about the ideal setting for rebound.
 

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interesting, xxguy. can you comment on how long the batteries last? have you checked your unit against a known guage for accuracy? got a link to the one you're using?

(y)
It's been two years. Haven't replaced batteries yet. Monitor is USB rechargeable.
The Fobo lasted a little over a year then put new in and all good again.


I bought mine for $25 but couldn't find more so I said $50 because I saw them for that and didn't want to get anyone's hope up.
Just saw this and the sensors look identical and the monitor display is a bit different but the unit looks the same.

Yes, checked against three different gauges. Within a pound of them. They are accurate. Plus I can check as I fill my tire with a hose that has a built in gauge.




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