Front tyre slip / cornering technique help (a bit long)

[JL]

Hi all, sorry but this is a bit of a long one and I hope it belongs in this section.

I'm not too sure whether this comes down to poor riding technique or tyre choice (or both) but I've just come back from a nice ride through the twisties and am curious as to why the front tyre likes to sometimes let go as I tackle the fairly tight hairpins at a decent pace.

This is what the right hand side of my front tyre looks like now (note the worn edge):

1 2 3 4

I am taking these tighter corners using a fairly late turn in and am wondering why the front tyre slips or 'skids' towards the outside before gripping again. I have had this happen on my 250cc Spada a few times as well, but notice it more on the 'rex. Is part of this due to a more forward inclined weight bias of the engine on the 'rex? How much does the tyre compound comes into play? I am using Battlax (sport touring) tyres, these are the only tyres I have experienced on the bike as I haven't had it very long. I only ran sport touring tyres on my Spada, so have never experienced a true 'sport' or performance tyre. Will I notice a big difference running a softer compound sport tyre on the front? (Please forgive my ignorance in regards to tyres, as you can see I haven't had much experience with them!) I am also wondering if I should be using the back brake a bit more through the turn to bring some weight to the rear, or turn in earlier.

I think that's about it, sorry for all the newbie questions but I thought I'd post here first in case there are some specific trx pointers any of you might be able to share with me! Cheers!

[honkdawillydahonk]

Is that a BT-020 you're running?

I think your problem is the tyre choice (and the fact it looks worn out) You're clearly riding beyond the tyres abilities!

Try running a BT-014 (or whatever the equivalent is now) front; the difference in grip will be vast compared to the -020.... and should work with a touring compound rear if you're that way inclined....

Or you could try proper sticky stuff which will blow your mind!

[HansJ]

Agree with Honk, but I am also curious how You're braking (since You talk of braking with the rear)?
How skilled/experienced are You?
Where do You apply/release the brakes?
Using both front/rear brakes?
What speeds are we talking about?
Only sliding in the hairpins, and if so, what's the difference from the other curves in terms of Your riding?
Any connections with ambient temperatures?
What pressures are You using front/back?

[John M]

Honk's pretty much nailed it JL. That is one pretty shagged looking tyre, and if there is one thing that freaks me out is a sliding front end so I think a visit to the tyre guy is in order. Even if most of your riding isn't scratching or track work you can never have too much front end grip. Go for a Pilot Power, Diablo Corsa or one of the sticky Metzelers, Bridgestones etc etc (everyone has their personal preference) and you won't believe how hard you can lean on the front end with complete confidence. And wear isn't really an issue on the front- you'll get plenty of k's out of any of these.

[youngy]

that tyre is knackered. a new one will be a whole lot better.

[JL]

Thanks for the quick input guys, I really appreciate it!

Honk: Yes, the tyre is a BT-020. Guess I'll have to start putting money aside for some upgraded rubber! I have always been curious about the difference it would make in cornering.

Hans: I've only been riding for the last 2 and a half years, the first 15 months was on a 250 due to restrictions and have only had my 'rex since September '07. I have ridden about 5-6 days a week during this period both commuting and play, so while still being a new rider I feel that I have built up a decent level of proficiency.
This is occurring on a set of mountain twisties that includes some small/medium sweepers and also some fairly tight hairpins. The speed limit is 100km/h throughout the whole section, with some slower 'recommended' (ie - not enforced) speeds on the tight stuff ranging from 25-35km/h. The sweepers are fine - pick brake point, apply front and rear, position body, release brakes and then turn bike, using constant throttle that builds up towards the exit. Even at full tilt with knee, boot and a LITTLE peg scraping the bike feels nice and solid through these corners ('rex trait?). The only problem here is when too much of the foot peg scrapes. Soon after I purchased the bike I was trying to find its limit when scraping the pegs. On a few occasions the back slid/stepped out when the pegs were scraping and I tried to lean it a bit more - I think this made too much weight transfer off the rear onto the peg , as it didn't look like the tyre was worn to the edge. Needless to say, I won't be trying those lean angles again in a hurry - not until I get my hands on some rearsets and a track day! Anyway, back to the hairpins - I go through the same procedure as above, but the flick from vertical to lean is much quicker. I don't go into the corner still braking, so aside from the tyre not coping was wondering if perhaps in the transition point between braking and acceleration I still have too much weight towards the front of the bike as I flick it and accelerate - hence causing the front to be pushed out and slide. Perhaps I should be braking a little earlier? The reason I was curious about using some rear brake through the corner was if it would help transfer some weight back to the rear so the front wouldn't have so much load on it. The tyres are warm (about an hours ride to destination) and at standard pressures and the road surface is warm too (25-30c).

Thanks for the questions, hope my reply makes sense!

[JL]

Geez, I spent so much time writing that reply that two more of you had already posted! Thanks

Guess I'll go and see someone about a new front next weekend, seems a shame as the tyre still seems ok, at least I'll still get a good 870km of freeway commuting done between now and then, but no scratchin' so I should be ok. Glad to hear that the sticky fronts can last a while - I was worried they might wear out too quickly. Might see if there is soft front that will work with my firmer rear (heh) as the current work location has me doing 174kms a day! Even though it's all straight it's still riding!

[Greg]

Looking at the tyre, and remembering what the Youngster said a while ago, I'm wondering whether the tyre is more old than shagged (notwithstanding the tread wear though)... The surface has a kind of 'polished' look to it, where I'd expect a tyre that's been pushed too hard to be more matt and have a more 'bobbled' and distressed look about it...

G

[HansJ]

You're going way too fast on public roads Kneesliding and peg scraping

Sounds like You already have the right thoughts, at least that's what I'd try. Braking a bit earlier, and accelerating smoothly earlier as well, this will move some weight off the front. Once near the limits, smoothness is the keyword. Maybe You should alter the line somewhat as well, going for less sharp more smooth lines. The brake hard, turn quickly, get on gas is more efficient on powerful 1000s, the TRX is more about curvespeed and the ability to get on power earlier.

[trixynut]

Also, check the type pressure: very important.

[Kevtrx849]

Watch out for scraping the pegs too much on the leftys as your alt cover is the next thing to touch down.

[youngy]

Ditto what Greg said................

and of course, if you're really actually sliding the front, you should be on the motoGP grid.

A new front 020 will be more than sufficient on the road. Don't bother with race spec rubber. And check your tyre pressures.

PS...been on the Old Speckled Hen all arvo, so anything here may be total bollocks.

[honkdawillydahonk]

A new front 020 will be more than sufficient on the road....

For knee / peg down? Rather you than me....

[youngy]

well you're probably right, but i used to scrape all sorts on Mac 90s. Can't do it on owt else. I was really trying to say that a new tyre will be a huge improvement over that knackered old thing that's on there.

[phuk72]

Old shagged tyre plus hard abuse equals overheating and loss of grip (indicated by the shiny bits).

IMHO, everyone gets far too excited about 020s. Yes they are great if all you want is distance and all year blandness (but even then they wear unevenly) but they are bloody lethal when part worn and then subjected to hard use.

The newer version (021s) have got good reviews but even so I would always opt for a stickier tyre unless ALL I wanted was long life. They black hops are all that keep you upright and so a few quid invested is worthwhile.

The dual compound Pirellis are the way to go if you want a decent compromise.