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pedalingfool
15-08-07, 03:06 PM
Just a quick one really, I recently went from my trusty BMW k1200rs to a fireblade as I thought I prefered sports bikes. I found that with the standard tyre pressurs 32 front 42 rear it handles slightly worse than an Epileptic attending a 70's style ice skating party. :'( When I get home I find myslef worried that I'm not pushing the bike yet the tyres are starting to melt and I'm not even close to the edges of the tyre. can anyone suggest something! HELP,

Just thought I would mention it does alright over 80 mph but under that it just doesn't feel chuckable!!!

Alternatively 4 sale 2007 HRC fireblade, handles badly but good at wheelies. feels slidey and generally don't want to go where you point it!

JamesHockley
15-08-07, 10:31 PM
42 psi in the rear seems a bit high, every sports bike I have owned has had about 36-38 in the rear. I run 33 front 36 rear in my TDM now, but then it is a TDM and not a Blade!!

furry-TLR
16-08-07, 01:30 AM
You didn't say what year your blade was...unless you meant it was 2007

http://www.bridgestone.eu/bfe/tyreSelectorController?page=motorCycle&dataToDispl ay=resultpage&step=4&country=Great%20Britain&hidde nCountry=Great%20Britain&hiddenMake=HONDA&hiddenMo del=CBR1000RR+Fireblade+&hiddenModelYear=06-&hiddenSite=Bridgestone%20Europe&locale=en_US

Anyway says 2.5 Bar front and 2.9 Bar rear.

1psi = 14.7psi atmospheric so...

Front = 36.75psi
Rear = 42.63psi

If the bike doesn't feel right, could well be down to the tyres you got on it?

I run 36psi front on mine and just over 40psi rear...any less than that I find the rear slumps and slides...and more than that and the rear end skips over everything.

You brought the bike from new or 2nd hand?

pedalingfool
16-08-07, 09:20 AM
I got it brand new, and have a little under 5000 miles on it now, it's funny because it seemed to handle a lot better with a pillion on the back, it does handle very well to be honest just not as good as i thought it would be, on the whole a little disappointed with it! :(

jj
16-08-07, 11:28 AM
drop the rear to about 38 if that does not work start looking at suspension set up as it has a huge affect on the way tyres work

pedalingfool
16-08-07, 12:05 PM
ok, I'll change my psi's to about 32 front 38 rear and see if I end up in a hedge, and get back. wish me luck this work lunch time! :)

kaka
16-08-07, 09:04 PM
been said before on this site but you could always take it to mhracing in corsham he will check your suspension settings for a small fee & advise on tyre pressures etc.
Mark is a nice guy to boot,set my bike up (even though it has useless forks)it has given me a lot more confidence turning in & winding on coming out of the corner.

furry-TLR
16-08-07, 10:56 PM
I'll ditto that MHracing rebuilt my Ohlins did a top job and then tweeked my settings A********

pedalingfool
17-08-07, 06:37 PM
Got the phone number? and I'll get it in and sorted!

Gav
17-08-07, 07:41 PM
As standard the pressures in the blade shoud be 36psi front 42psi rear...
But i would run 34psi front and 36psi rear to optimise tyre life and grip

darth_vader
17-08-07, 09:06 PM
my zx10r has similar recommended tyre pressures.i found that with the pirelli corsa pro's now fitted,i run mine @ 33 front and back they feel much better .the lower the tyre pressure the quicker the tyres heat up.

play around with the pressures and see what suits you.best of luck.

furry-TLR
17-08-07, 11:26 PM
Got the phone number? and I'll get it in and sorted!

http://www.mhracing.com/

Phone him or even better just pop in and visit, over by Corsham next to the MOD site round the back :)

I wouldn't recommended running too low psi, will make the bike sluggish and understeer...go see him he's a genious when it comes to getting bikes to handling right 8-)

darth_vader
20-08-07, 08:06 PM
racers run low tyre pressures to generate more heat.go ask some one who knows.

Ghost
20-08-07, 09:06 PM
racers run low tyre pressures to generate more heat.go ask some one who knows.

I would suggest racers run lower than hand book recommendation but not necessarily just 'low' tyre pressure. I recommend you take expert advice depending on what you want to do, road solo, road pillion, track or whatever. With respect, posting on here you are going to get 101 different versions of the correct answer!

pedalingfool
21-08-07, 11:26 AM
well, I'm going to take the bike to get it looked at to make sure everything is ok. but FYI, I went to the nurbugring last year, in an Elise. I was driving the beast following someone in what looked likea very standard BMW M3 CSl, so anyway after I span off on Miss hit miss avoiding the armco by approxiately 8MM's, I got back to the main car park to find a very smiley Jason Plato, a thoroughly nice bloke. he advised me that in fact the best and only way to set your tyre pressure is to put them at the reccommended manufacturer's pressure when the tyre is hot. As so you all know, a tyre actually will run cooler at lower pressure and not melt, it just heats up faster. and then you get the recommended pressure and the tyre wil then actually work. So I have been to see a friend who races mini moto, yes, MiniMoto, he won the british championship and said the only way to do it is ride until the tyre is hot and then set the tyre pressure to manufacturer recommended, then ride hard again, check as the cool air you put in will have heated up, re adjust pressure, Now, he said go home leave the bike over night, check tyre pressures, and from now on only pupm them to those pressures when they are cold before you ride!!! I hope that made sense! I'm going to try this if we get some decent weather and I will let you all know. rob.

darth_vader
21-08-07, 06:15 PM
racers run pressures as low as 29 psi.i set mine by trial and error.i found 33 front and back suited me best.