Lean Angle

[lewis_walker]

Hi guys, been a while since I posted.
Thanks to PaulNZ for helping me fix my throttle cable / tube I have enjoyed many hours on my 1986 VFR750.
Thoroughly enjoy the bike, and regularly do Paekakariki Hill on it whenever the weather is conducive.

The VFR is my first "Old Bike" - I've previously ridden a Bandit 1200, SV1000, Fazer 600. The VFR feels really good around the twisties, but I've no idea where the handling limits are on the thing. The little (130) section back tyre sort of makes me nervous! Should I be nervous of it? Where are the limits on a bike like this? Can I scrape the pegs under a steady throttle? I went pretty hot (compared to my normally pretty sedate riding) around a signed 35kph bend at 80kph the other day, with a fair lean angle and the bike certainly felt pretty planted. But I don't want to find out the HARD WAY!!

Please, anyone - any advice?

[onearmedbandit]

From what I understand, it doesn't matter how wide your tyres are as far as lean angle is concerned. Take the lean angles achieved on 125GP bikes, very thin tyres but huge lean angles. What a wider rear tyre does give you, or more so the bike, is more rubber on the ground while leant over, hence why powerful road bikes have fuck-off section rear tyres compared to even the above mentioned 125GP.

Also, the wider your rear tyre the more 'offset' happens as you lean, meaning the bikes chassis moves in relation to the contact patch. Some riders will notice an improvement from dropping to 180 section rear hoop from a 190, although whether this is due to the 'quicker' turn-in rate of the smaller section, or improved chassis alignment I'm not sure.

Put good rubber on your bike and I'd say you should be able to grind pegs all day long.

[FROSTY]

The narrow tyre aint gonna be a problem
I was racing on a 100/80/19 front and a 120/80/18 rear with no dramas.
Those viffers are a really good bike but I would have pretty sticky rubber if you plan to ride it hard.

[Windy]

A bike would actually handle better if both front and back tyres were the same section (the bigger the back tyre, the more it has to slip out of line with the front to go round the corner) but you want more rubber at the back because that's where the bike gets it's drive. VFR's aren't hugely powerfull, by todays standards, so you don't need blinging great 180 section tyres. Get some good rubber and enjoy people wondering how the f*ck you went so fast on an 'old' bike.

[Paul in NZ]

130 section? Luxury.....

I have a 110 on the Guzzi... Beautiful...

[Toast]

I read in a magazine that the wider the rear tyre...all else being equal (speed, bike, rider, rim matching, profile, etc)...the more the bike has to lean for a given speed, which isn't very cool for many reasons.