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Old 07-23-2018, 04:44 PM   #16
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What riding errors do u see?

Closing the throttle there is correct. If anything, it was closed too soon. Perhaps it was closed too fast.
Admittedly, it's been a number of years since I was at BW, but I'm not sure why a rider would be on the gas and then suddenly chop it there. To me, that's an error.
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Old 07-23-2018, 07:01 PM   #17
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If your drive to Riverside is strong, u gotta slow down at some time to make it through that corner. A 600 can just roll off until you get near 1:51-52. A fast 1000 needs to brake for sure. A racer should of course be WOT through the kink before Riverside. To go really fast, u need to turn in a little while WOT too.

But ya, “suddenly” may always be a mistake cuz it asks for grip without creating the grip by loading the front smoothly. Good engine braking control can help mitigate that. Who knows if that was the cause.
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Old 07-24-2018, 02:16 PM   #18
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Originally Posted by Smash Allen View Post
i was pitted with ian in the garage

he was on bridgestones, we (not ian, he was loopy all day after that) were thinking at the time it was a bad front tire

if not the tire, i would be interested to find out the condition of the suspension / suspension fluid

it reminds me of a tank slapper, but going 'up and down' instead of 'side to side'
A couple of my friends have switched between pirelli and 'stones and they frequently complain about chatter with the 'stones.

They don't really adjust their suspension for the stones, and i think they're a stiffer tire causing those issues for them. They have no chatter with the pirelli.

I have other friends going very fast with little issue on stones aswell though so i guess what i'm saying, has he always run stones or was it a recent change?
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Old 07-25-2018, 09:00 AM   #19
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So, as far as I can tell, the main cause of this crash was my error in going in too fast.

I remember that day, this was the first day of a new AFM practice group, I had previously been in 4 and this day they combined 4 and 5. So when Andrew Lee went by me like I missed shift, I thought, "Crap, I'm so slow." I felt pressure, way more that I should have.

I had also made a fairly large adjustment in the front tire pressure, and it seemed to help a lot. So much so that I was really having fun pushing the front to it's new limit. Riverside being so long, it gives you a lot of time to sneak up on the limit, and I was enjoying the new feedback. The tires at this point were pretty worn, i was planning to get a new set later that day.

My forks at this point were about a year old from the last rebuild, and I could notice they were not as good as they had been previously.

But, this was not my first practice session, nor the first lap of the session. I knew the condition of my equipment. I think was just riding over my head, and out of my regular experience, this was only my fifth AFM race after all.

So, mid corner, I'm already near the limit of the front, but I know that near the exit it tightens up a bit and it gets bumpy, so I roll off to try to slow down a bit, and the front gave.
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Old 07-25-2018, 09:40 AM   #20
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So, as far as I can tell, the main cause of this crash was my error in going in too fast.

I remember that day, this was the first day of a new AFM practice group, I had previously been in 4 and this day they combined 4 and 5. So when Andrew Lee went by me like I missed shift, I thought, "Crap, I'm so slow." I felt pressure, way more that I should have.

I had also made a fairly large adjustment in the front tire pressure, and it seemed to help a lot. So much so that I was really having fun pushing the front to it's new limit. Riverside being so long, it gives you a lot of time to sneak up on the limit, and I was enjoying the new feedback. The tires at this point were pretty worn, i was planning to get a new set later that day.

My forks at this point were about a year old from the last rebuild, and I could notice they were not as good as they had been previously.

But, this was not my first practice session, nor the first lap of the session. I knew the condition of my equipment. I think was just riding over my head, and out of my regular experience, this was only my fifth AFM race after all.

So, mid corner, I'm already near the limit of the front, but I know that near the exit it tightens up a bit and it gets bumpy, so I roll off to try to slow down a bit, and the front gave.
how can that be if Andrew Lee went in tons faster? extra speed might have been the immediate cause, but reducing it is not the solution since we are talking about racing. unless u are at lap-record pace, theres always room to go faster with the proper skills and equipment.

1yr on a set of forks won't make them perform noticeably different, esp if you have a set of aftermarket carts. they keep the oil really clean. and 1yr isnt enough time to make the oil break down or anything in a set of forks.

going up in front tire pressure can be a good way to reduce chatter. it also can help the bike turn better, esp when hard on the brakes. the drawback to this is that slow experts and novices might have a hard time getting the front tire hot enough w/ a higher pressure. but u didnt say u went up in pressure.

its possible that your front tire was too worn to hold that higher pace, but I doubt it. it goes without saying that someone could have gone faster on your front tire. how many sessions/days did it have on it?
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Old 07-25-2018, 11:56 AM   #21
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how can that be if Andrew Lee went in tons faster? extra speed might have been the immediate cause, but reducing it is not the solution since we are talking about racing. unless u are at lap-record pace, theres always room to go faster with the proper skills and equipment.

1yr on a set of forks won't make them perform noticeably different, esp if you have a set of aftermarket carts. they keep the oil really clean. and 1yr isnt enough time to make the oil break down or anything in a set of forks.

going up in front tire pressure can be a good way to reduce chatter. it also can help the bike turn better, esp when hard on the brakes. the drawback to this is that slow experts and novices might have a hard time getting the front tire hot enough w/ a higher pressure. but u didnt say u went up in pressure.

its possible that your front tire was too worn to hold that higher pace, but I doubt it. it goes without saying that someone could have gone faster on your front tire. how many sessions/days did it have on it?
The change was down in pressure. I had been trying to stay close to settings that I got from the bridgestone guy and adjusting by about half a psi or so, but I kept losing pressure (meaning that it would be about 1/2 pound lower when i got off the track). So I dropped it like 3 psi, and that made a big difference.

My forks are just stock with race tech valving. This is still my first track bike, I've never actually ridden a bike with "good" suspension, so I have no idea how good they ought to be.

No one passed me at Riverside in that session, I think it was the previous session and they went by on the front straight (i was just guessing that it was Andrew Lee, but now that I have thought about it, it was probably Chris Siglin). My weakest point has always been accelerating out of corners.

I'm not saying that I went into riverside faster than anyone could, I'm saying that I went in faster than I could.

I think if i find myself in that situation again, I will try to run wide first and decelerate second.
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Old 07-25-2018, 12:06 PM   #22
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The change was down in pressure. I had been trying to stay close to settings that I got from the bridgestone guy and adjusting by about half a psi or so, but I kept losing pressure (meaning that it would be about 1/2 pound lower when i got off the track). So I dropped it like 3 psi, and that made a big difference.
thats bad, thats real bad. it both suggests u arent getting any heat into the front tire and/or u are losing a TON of air. rem, the pressure should be higher when u get off track - at least 3psi higher for almost everyone. u probably shouldnt have ridden the bike like that.
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Old 07-25-2018, 12:31 PM   #23
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thats bad, thats real bad. it both suggests u arent getting any heat into the front tire and/or u are losing a TON of air. rem, the pressure should be higher when u get off track - at least 3psi higher for almost everyone. u probably shouldnt have ridden the bike like that.
Ignorance is bliss.

I must mention that I used the woodcraft warmers on the hot setting, I don't recall the numbers now, but the temp was not all that much less than the temp they recommended for just off the track. I don't think it was leaking, because it would go back to the same pressure after being on the warmers.
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Old 07-25-2018, 12:50 PM   #24
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oh I read your prev post wrong, thinking u had a leak. sry.

ya, u prob aren't getting enough heat into the tire. u just gotta brake harder and later for all the braking corners.

def keep an eye on your front tire pressure off the track. u can probably stick with your -3psi setting for now so that u actually get a rise. but as u get faster, ull likely want to bump that back up. although, that assumes the pressure the rep gave u is what all the fast people use.
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