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Andrew Longman
06-04-06, 06:27 PM
Watching AMA at RA, I am really looking forward to my pilgrimage there in September.

But it is the first time I've watched bikes on a track I know well. Are brake points for bike a lot earlier than what is typical for a Champcar or Atlantics?

Seems so. I would have thought the lower speed, lighter weight, ability to bank, and discs about the same size would have made it about the same or at least closer.

I guess the smaller contact patch makes the difference. Be patient, I'm still learning this bike thing. :gomer:

coolhand
06-04-06, 06:56 PM
The biggest differnce between the bikes and cars is the overall contact patch. Two skinny wheels means longer breaking zones and slower cornering.

however they are faster at top speed. The best track to do a comparision is Catalunya. F1 v. MotoGP. The bikes clock higher in the speed traps there but the F1 cars fly faster through the twisty parks. Its due to the combination of better grip, downforce and braking. The lack of those is why the bikes are faster on the top end, less drag and friction.

2 years ago I looked into this because I had no clue about the performance difference between motogp and F1.

DagoFast
06-04-06, 07:07 PM
Very different chassis dynamics at work. Bikes have huge engine and braking power. It's the rider delicately balancing it that is the attraction.

The contact patch is smaller, but there is enough traction and braking force to lift the rear tire up off the track when the bike is upright and still going straight. (watch some MotoGP in slo-mo, 3-4" of daylight under the rear tire at the end of a 200 MPH straightaway!)

When its leaned over in the turn, too much front brake will cause a "low side" where the front wheel slides and the bike drops to the ground. Some of the better/stronger riders can sometimes, with a little luck, save it by using thier knee as leverage to lift the bike back up onto the front tire after they release the brakes.

Conversely, under acceleration the front end can be easily lofted if too much throttle is used. No traction control here, just very judicious use of the right wrist.

If too much throttle is used too early, while still leaned over, a very cool drift or slide is attained. The downside, especially with radials, is if the rear tire hooks up suddenly a spectacular* event known as a highside occurs.

(*spectacular for the veiwers anyway)

The MotoGP race from Mugello was the best race on TV today. I've got tickets to the USGP at Laguna Seca in July. :)

coolhand
06-04-06, 07:13 PM
dago brings up good points about the Driver. Watch them during the race and how they clammer around the bike shifting their weight inorder to increase traction. cool stuff.

I will do my best to make it to the USGP. Outisde of the message board world I don't know anyone who has heard of motogp.

Fio1
06-04-06, 07:29 PM
Having raced against bikes at Mulholland and the Nurburgring Nordschleife quite a few times in cars I could tell you first hand what the main difference is. On the straights they are gone, but they park it in the corners (like someone else said contact patch being smaller) and yes their braking zone is a lot before then a good car (CCWS) eventhough they weight 20% of a CCWS. This scenario becomes kind of anoying for both the car and bike. You try and pass under braking, take off in the corner and homeboy repasses you on the straight.....If you know that there will be a lot of corners coming up, then you get a little nasty and block the guy on the bike, because you know you won't see him again. But, if a bike is ahead of you in a series of corners, then it's like driving with a toyota prius infront of you.... :mad:

oddlycalm
06-04-06, 07:52 PM
Outisde of the message board world I don't know anyone who has heard of motogp. Yeah, why would the mainstream media want to put out any information on a sport that US riders have dominated for much of the last 30yrs and in which a US rider has had the points lead for the championship most of the season.... :gomer:

The shame of that is that the racing today in MotoGP is as good as it's been at any time during the last 40+yrs that I've been watching and there isn't much else in the racing world that I can say that about.

I do actually know quite a few people that have followed GP motorcycle racing since they are riders themselves. Remember, a lot of those goofs out there on the streets on sport bikes actually know about MotoGP and there are quite a few these days.

oc

eiregosod
06-04-06, 08:51 PM
Putting the knee down is another skill the pros have. When they go through the corner, the bike leans over, and the rider can put his inside knee on the ground. Titanium protective gear is worn around the knee, It would be fun to see the sparks if they ran motorbike races at night.

NismoZ
06-04-06, 09:19 PM
Even at Road America this weekend the Superbikes were hitting over 195 mph (according to the announcer) which is ChampCar territory, but the 2:12 lap times are WAY of CC's 1:41.

coolhand
06-04-06, 09:45 PM
Having raced against bikes at Mulholland and the Nurburgring Nordschleife quite a few times in cars I could tell you first hand what the main difference is. On the straights they are gone, but they park it in the corners (like someone else said contact patch being smaller) and yes their braking zone is a lot before then a good car (CCWS) eventhough they weight 20% of a CCWS. This scenario becomes kind of anoying for both the car and bike. You try and pass under braking, take off in the corner and homeboy repasses you on the straight.....If you know that there will be a lot of corners coming up, then you get a little nasty and block the guy on the bike, because you know you won't see him again. But, if a bike is ahead of you in a series of corners, then it's like driving with a toyota prius infront of you.... :mad:

If I am reading you right, you are saying you raced cars vs. bikes? cool, what circuit or club is this?

DagoFast
06-05-06, 12:22 AM
Yeah, why would the mainstream media want to put out any information on a sport that US riders have dominated for much of the last 30yrs and in which a US rider has had the points lead for the championship most of the season.... :gomer:

The shame of that is that the racing today in MotoGP is as good as it's been at any time during the last 40+yrs that I've been watching and there isn't much else in the racing world that I can say that about.

I do actually know quite a few people that have followed GP motorcycle racing since they are riders themselves. Remember, a lot of those goofs out there on the streets on sport bikes actually know about MotoGP and there are quite a few these days.

oc

On a world wide basis, the crowds and TV audiences are huge.

But don't underestimate us stoopid 'mericuns.
In it's first year back in the USA after a many year absence, the MotoGP race at Laguna Seca was a sell out last year. I believe that was the first time in the history of the track a sell out has ever happened.

The track is closed right now while they are making many many upgrades in anticipation of an even larger crowd this year.

eiregosod
06-05-06, 12:43 AM
There were always massive crowds for the World Superbikes at laguna Seca.

The crowds were so big that the size pissed off the president of the AMA

cameraman
06-05-06, 01:11 AM
But don't underestimate us stoopid 'mericuns.
In it's first year back in the USA after a many year absence, the MotoGP race at Laguna Seca was a sell out last year. I believe that was the first time in the history of the track a sell out has ever happened.

It was all the Canadians driving down from BC...

coolhand
06-05-06, 01:12 AM
One of the main challenges that confronts a MotoGP motorcycle rider and designer is how to translate the machine's enormous power - over 240 horsepower (179 kW), through a single tyre-contact patch roughly the size of a human hand. For comparison, Formula 1 cars produce up to 750 bhp (560 kW) from their 2.4 litre engines but have 10 times the tyre contact surface. Because of this difficulty, MotoGP is perhaps unique in modern motor sport in that teams will often deliberately detune their engines to allow their riders a chance to control them, with most not making more than the 180 to 190 bhp (135 to 140 kW) of the front-running two-stroke bikes.

found this on wikipedia

claims F1 cars ahve 10 times the contact patch.

Fio1
06-05-06, 01:43 AM
If I am reading you right, you are saying you raced cars vs. bikes? cool, what circuit or club is this?

This is not organized racing or track day. If it were I believe this club would be called widow maker. This is Saturdays or Sundays on Mulholland or Sunset; once in a while you'll see guys on bikes wearing full leathers. And the Old Nurburgring open 'tourist' days. Now that is a little bit more crazy. Serious bike riders wearing full leathers and a mix of tuned Porsches, normal street sedans going slow and the occational tour bus. I prefer the organized track days or school at the Nurburgring too much going on with bikes and stuff to learn anything.

Andrew had a very legit question. Because before I met up with some guy on a Ducati on Sunset one afternoon 10 years ago, I had no idea bikes braked so early and didn't have the corner speed you think they do when watching races on TV. You watch bike racing on TV and looks stupid fast (not that it isn't), but you have no idea that they only do F.Mazda times. The guy I 'raced' that first time could ride and did some club racing at Willow Springs, we chatted afterwards, so it's not like he was a complete novice. I just couldn't believe I past the guy on the outside in a 86 Toyota MR2 like that and pulled away in the corners.

Warlock!
06-05-06, 02:18 PM
Even at Road America this weekend the Superbikes were hitting over 195 mph (according to the announcer) which is ChampCar territory, but the 2:12 lap times are WAY of CC's 1:41.
Don't the bikes use the chicane after the Carousel at RA? That doesn't account for all the time lost to a champcar, but it adds a chunk...

Andrew Longman
06-05-06, 02:32 PM
Don't the bikes use the chicane after the Carousel at RA? That doesn't account for all the time lost to a champcar, but it adds a chunk...

Yes.

Just a WAG but with the added distance, braking and lost momentum I say it add about 6 seconds

Ankf00
06-05-06, 02:34 PM
contact patch, only 2 wheels & discs instead of 4, lack of aero grip, having to balance the brakes such that both wheels stay planted for maximum brake force, and also needing to slow down further than formula cars for corner entry because of that whole aero thing...

you can see the bikes completely lurch forward, pushing down on the fork under braking.

oddlycalm
06-05-06, 04:25 PM
Don't the bikes use the chicane after the Carousel at RA? That doesn't account for all the time lost to a champcar, but it adds a chunk... You're right, and it makes a comparison pretty hard to do. We could probably find lap times from the last Champ Car race at Laguna Seca and the MotoGP lap times from last season though.

coolhand is right that the best track to do a comparision is probably Catalunya due to both series using the same track configuration.

AMA Superbike compared to MotoGP is a totally different animal. One is production based and the other is no holds barred with huge budgets ala F1.

oc

Fio1
06-05-06, 09:18 PM
Laguna Seca runs the same config for bikes and cars. The 500 class ran the same times as the new Formula Mazda, 1:22's.

stroker
06-05-06, 11:28 PM
Yes.

Just a WAG but with the added distance, braking and lost momentum I say it add about 6 seconds

A lap time of roughly 2:06 at RA (on the original course) would put a Superbike right up with Denny Hulme in the M8F McLaren of 1971.

I can't get my brain wrapped around that...

Ankf00
06-06-06, 12:46 AM
Laguna Seca runs the same config for bikes and cars. The 500 class ran the same times as the new Formula Mazda, 1:22's.
just fyi: there's no more 500 class

Fio1
06-06-06, 12:54 AM
just fyi: there's no more 500 class

Well, there is in my book! 2-Strokes forever!!!!!!!!!!!!! :thumbup:

RacinM3
06-06-06, 02:31 PM
Fio has it right.....it's why the bikers are always pissing me off over Angeles Crest Hwy. They're fast on the straights but you have to dodge the anchor when the turns come.

oddlycalm
06-06-06, 03:17 PM
If anyone has the time they can compare lap times at Laguna Seca between MotoGP and AMA Superbike at last years race then compare to the last time Champ Cars ran there. What you are going to see though is that Champ Cars ran laps many seconds faster than MotoGP and they in turn were much faster than AMA Superbike.

BTW, as long as there is no real competition to the Yoshimura Suzukis the AMA races are going to look a lot like like Ferrari of 1998-2004 but without team orders.

oc

Ankf00
06-06-06, 03:52 PM
Well, there is in my book! 2-Strokes forever!!!!!!!!!!!!! :thumbup:
this is true, 500's, cheap privateer engine leases, and stacked grids...