Interesting thread, I had similar when I initially tried the bike at snetterton. Off to Jerez in a few weeks, will ensure abs is off, and have changed pads and fluid beforehand too. Looking forward to theee days of getting to grips with everything!
Bike ?weaving? under heavy braking on track
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fast_ryan
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T5 Portim?o
For T5 at Portim?o try taking it in 2nd gear. The corner entry here is difficult to get right and the tarmac braking area is rippled with bumps which tests front tyre stability. If the ABS is on it can momentarily transfer weight from the front to the rear which you don't want to happen as it unsettles the bike. Down-shifting early is beneficial as you will find using the engine braking helps you to get to the apex. Once you've avoided losing the front end you then need to guide the bike around the inside of the curb as tight as you can. You then use all of the track on exit at full throttle as you accelerate out of the corner for yet another elevation change.
For T5 at Portim?o try taking it in 2nd gear. The corner entry here is difficult to get right and the tarmac braking area is rippled with bumps which tests front tyre stability. If the ABS is on it can momentarily transfer weight from the front to the rear which you don't want to happen as it unsettles the bike. Down-shifting early is beneficial as you will find using the engine braking helps you to get to the apex. Once you've avoided losing the front end you then need to guide the bike around the inside of the curb as tight as you can. You then use all of the track on exit at full throttle as you accelerate out of the corner for yet another elevation change.
Thanks, though I have never tried anything other than 2nd as it is about 45-50mph for me.
- Alex
- Alex
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cropsprayer
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So you just changed your ABS setting and that made all that difference?
It still gets squirrelly but its much more under MY control.
The weight transfer /suspension can further improve things but its definitely more stable now.
- Alex
cropsprayer
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Ok thanks Alex. I’ve not fully resolved my issue yet despite having new springs fitted to forks and tweaking suspension settings. Enjoy the rest of your time at Portimao!
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SC2's have a tendency for this as the carcass is softer. SC1's get rid of it. Allows much heavier braking but not so forgiving in all temperatures. Always a trade off. J
Never got that lap record, sadly...lol
I just wanted to quickly evidence that the ABS was having an effect, but let me just agree with the above, other factors matter as well, tyres/suspension etc
These were 2x 2:06 laps with RACE ABS and 2x 2:04 laps with SLICK ABS. No matter how well or badly I was riding you can see the ABS spikes which only occur on the 2:06 laps. The rear brake is totally off on the RACE ABS laps at this point. It also has the TPS open at the same point
Simple fact was it felt more under control in SLICK ABS mode. My braking was more consistent, and I could use less lever pressure to get the same result in terms of deceleration.
I just wanted to quickly evidence that the ABS was having an effect, but let me just agree with the above, other factors matter as well, tyres/suspension etc
These were 2x 2:06 laps with RACE ABS and 2x 2:04 laps with SLICK ABS. No matter how well or badly I was riding you can see the ABS spikes which only occur on the 2:06 laps. The rear brake is totally off on the RACE ABS laps at this point. It also has the TPS open at the same point
Simple fact was it felt more under control in SLICK ABS mode. My braking was more consistent, and I could use less lever pressure to get the same result in terms of deceleration.
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What about switching off ABS completely?
Yup, hold down the button on the lhs switchgear...
cropsprayer
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Just wanted to update on this one as it’s now resolved and many people took time to try and help me. The issue was the bottom headstock bearing had failed......basically the bearing race had cracked / broken up. I’ve replaced the bearings with tapered bearings and all is now fully sorted. Someone did ask if I had checked these earlier on in the thread but I was advised the way to do so is to get the bike off the ground and check for front wheel play and/or notchiness when moving the steering. I had neither so be warned the only way to properly check is to remove the front end and visually inspect the bearings.
Thanks for updating us. Valuable experience shared.
