I also can see problems if you try to calibrate your rev counter against a fixed speed for any particular speed.
As has been said, two-strokes would need to keep slipping the clutch and blipping to clear down and I am not sure if the lowest gearing on a 4-speed classic Manx Norton would cope with about 37mph without slipping the clutch, on TT course gearing.

Apparently its the ACU Road Race Committee who have brought this in, not the FIM.

I had my mate on the phone this morning blowing his stack after receiving the memo with his entry, he'd been chasing people on the phone trying to talk some sense into the powers that be, and asking them for suggestions on how to keep a highly strung 250 to 60kph successfully without needing a plug change at the end of the pit lane!

It gets worse.......we've now heard a rumour that the 60kph limit starts at the end of the police station road!! which is the very beginning of the concrete apron for the pits, if this is the case we will have a combination of bikes slowing to 37mph on the actual road itself and traffic going straight through doing around 145 - 150mph within a few feet of the slowing bikes.

Hmmm that'll make for safer racing then!!

(28-07-2009, 12:04 PM)Manx Mist Wrote: Apparently its the ACU Road Race Committee who have brought this in, not the FIM.

I had my mate on the phone this morning blowing his stack after receiving the memo with his entry, he'd been chasing people on the phone trying to talk some sense into the powers that be, and asking them for suggestions on how to keep a highly strung 250 to 60kph successfully without needing a plug change at the end of the pit lane!

It gets worse.......we've now heard a rumour that the 60kph limit starts at the end of the police station road!! which is the very beginning of the concrete apron for the pits, if this is the case we will have a combination of bikes slowing to 37mph on the actual road itself and traffic going straight through doing around 145 - 150mph within a few feet of the slowing bikes.

Hmmm that'll make for safer racing then!!

More rumours-Have heard there will be a line painted down the road-incoming riders keep to the left, and riders not coming into the pits will keep to the right of this line. A rumour about the exit of the pits is that a line will be painted down the road as far as the bridge by the paddock return lane. Riders exiting the pits keep to the left of the line, and riders who are on a 'flying' lap keep to the right of the line.

(28-07-2009, 12:04 PM)Manx Mist Wrote: Apparently its the ACU Road Race Committee who have brought this in, not the FIM.

I had my mate on the phone this morning blowing his stack after receiving the memo with his entry, he'd been chasing people on the phone trying to talk some sense into the powers that be, and asking them for suggestions on how to keep a highly strung 250 to 60kph successfully without needing a plug change at the end of the pit lane!

It gets worse.......we've now heard a rumour that the 60kph limit starts at the end of the police station road!! which is the very beginning of the concrete apron for the pits, if this is the case we will have a combination of bikes slowing to 37mph on the actual road itself and traffic going straight through doing around 145 - 150mph within a few feet of the slowing bikes.

Hmmm that'll make for safer racing then!!

I really think people need to think and apply a little common sense before getting too carried away.

Does it really matter who introduced it? At the end of the day the FIM were responsible for the ludicrous chicane at Silverstone. You only have to look at the hoops Silverstone has to go through at the moment to see how the FIM can work.

Phil Taubman is a sensible guy he wouldn’t issue a statement that was completely inaccurate. If they are going to use transponder loops the top won’t be up by the police station road. For the transponders to work effectively they need to be roughly at right angle to the direction the bikes are travelling this would make sense as the original statement says it will be just before the start of the Armco. About where the stop box is now! So pulling off the road should be safer.
I suspect somebody has heard about the lines to mark the entry and exit lanes for the pit lane put 2+2 together and come up with 47!

Except for the classics or if a race is shortened to three laps the bikes passing each other shouldn’t be a problem as over 4 laps the difference between to front and back of the field isn’t big enough to cause the leaders to be in amongst the backmarkers during pit stop time. At least not at the Manx!

As for your mate’s problem with the 250, he should be grateful he’s not ridding a 125! At least he’s got a much bigger spread of power than me. I know what the answer from the FIM/ACU (whichever you chose to believe is behind this) will be “they manage it in GP’s with the super highly strung Aprilia’s”.

It’s here, for good, or for bad and the MMCC are doing everything they can to help. I’m sure if people are having major problems or it’s causing serous issues then they will try to change things as much as they can to help.
Equally I’m sure that constructive ideas will be welcomed.

I also think the FIM/ACU is using this as a test for the TT where the problem is worse and the problems it will cause are worse.

As for what I think of it. Despite all the problems I think this is a real improvement over the stop box and probably long overdue.

Anybody who is interested should look at the FIM web site it outlines all the requirements for pit lanes, entry and exit lanes and specifies a speed limit of 60kph.

(29-07-2009, 01:49 PM)smokey125 Wrote: I really think people need to think and apply a little common sense before getting too carried away.

Does it really matter who introduced it? At the end of the day the FIM were responsible for the ludicrous chicane at Silverstone. You only have to look at the hoops Silverstone has to go through at the moment to see how the FIM can work.

Phil Taubman is a sensible guy he wouldn’t issue a statement that was completely inaccurate. If they are going to use transponder loops the top won’t be up by the police station road. For the transponders to work effectively they need to be roughly at right angle to the direction the bikes are travelling this would make sense as the original statement says it will be just before the start of the Armco. About where the stop box is now! So pulling off the road should be safer.
I suspect somebody has heard about the lines to mark the entry and exit lanes for the pit lane put 2+2 together and come up with 47!

Except for the classics or if a race is shortened to three laps the bikes passing each other shouldn’t be a problem as over 4 laps the difference between to front and back of the field isn’t big enough to cause the leaders to be in amongst the backmarkers during pit stop time. At least not at the Manx!

As for your mate’s problem with the 250, he should be grateful he’s not ridding a 125! At least he’s got a much bigger spread of power than me. I know what the answer from the FIM/ACU (whichever you chose to believe is behind this) will be “they manage it in GP’s with the super highly strung Aprilia’s”.

It’s here, for good, or for bad and the MMCC are doing everything they can to help. I’m sure if people are having major problems or it’s causing serous issues then they will try to change things as much as they can to help.
Equally I’m sure that constructive ideas will be welcomed.

I also think the FIM/ACU is using this as a test for the TT where the problem is worse and the problems it will cause are worse.

As for what I think of it. Despite all the problems I think this is a real improvement over the stop box and probably long overdue.

Anybody who is interested should look at the FIM web site it outlines all the requirements for pit lanes, entry and exit lanes and specifies a speed limit of 60kph.

That's all very well Smokey, but can you suggest how it is possible to speed control a classic? Of course they manage it at GPs and WSB - with an ECU it isn't a problem, but when you haven't even got a speedo? I can do some calculations based on wheel diameter etc. to use the tacho, but there is bound to be a large margin for error, and race day is going to be a bit late to find out just how large it is!

(29-07-2009, 04:38 PM)superted Wrote: That's all very well Smokey, but can you suggest how it is possible to speed control a classic? Of course they manage it at GPs and WSB - with an ECU it isn't a problem, but when you haven't even got a speedo? I can do some calculations based on wheel diameter etc. to use the tacho, but there is bound to be a large margin for error, and race day is going to be a bit late to find out just how large it is!

Only to a certain extent superteb. On the four strokes yes but the two stroke GP 250 and 125’s don’t have electronic speed limiters. They do exactly what you suggested. Calculate overall gearing and get a rev’s based reading the most inaccurate part of this is going to be your measurement of wheel diameter and rev counter accuracy. At the end of the day most rev counters are more accurate than a speedo and most road bike speedo’s are set up for a standard bike any change away from that would create inaccuracies. The other problem with that is speedo must be tapped up so would be no use anyway.

What they do have at GP’s since not all bikes have speed limiters is speed signs like you get on road works. I believe the MMCC is looking at installing these as well.

There are plenty of other solutions if you think latterly. I am working on one at the moment that is a simple self-contained unit that could be fitted to any bike. However the lack of time to build and test means I probably won’t get it done for this year.

For most of the classics it won’t be a problem so I guess your on a 250 two stroke? Having said that we worked out the revs on the 350 Ducati I will be riding in the Junior classic and it’s getting towards 6000rpm. So you could still ride it with a reasonable margin of error.

As an idea how about suggesting that they put signs up on the return road during practice week will give people a chance to test speed limiters/calculations.

(29-07-2009, 10:10 PM)smokey125 Wrote: Only to a certain extent superteb. On the four strokes yes but the two stroke GP 250 and 125’s don’t have electronic speed limiters. They do exactly what you suggested. Calculate overall gearing and get a rev’s based reading the most inaccurate part of this is going to be your measurement of wheel diameter and rev counter accuracy. At the end of the day most rev counters are more accurate than a speedo and most road bike speedo’s are set up for a standard bike any change away from that would create inaccuracies. The other problem with that is speedo must be tapped up so would be no use anyway.

What they do have at GP’s since not all bikes have speed limiters is speed signs like you get on road works. I believe the MMCC is looking at installing these as well.

There are plenty of other solutions if you think latterly. I am working on one at the moment that is a simple self-contained unit that could be fitted to any bike. However the lack of time to build and test means I probably won’t get it done for this year.

For most of the classics it won’t be a problem so I guess your on a 250 two stroke? Having said that we worked out the revs on the 350 Ducati I will be riding in the Junior classic and it’s getting towards 6000rpm. So you could still ride it with a reasonable margin of error.

As an idea how about suggesting that they put signs up on the return road during practice week will give people a chance to test speed limiters/calculations.

Only playing devil's advocate, as the two bikes I'm looking after shouldn't need to go in there - if they do we're already in big trouble I'm sure you can guess what breed they are

(30-07-2009, 06:46 AM)superted Wrote:

(29-07-2009, 10:10 PM)smokey125 Wrote: Only to a certain extent superteb. On the four strokes yes but the two stroke GP 250 and 125’s don’t have electronic speed limiters. They do exactly what you suggested. Calculate overall gearing and get a rev’s based reading the most inaccurate part of this is going to be your measurement of wheel diameter and rev counter accuracy. At the end of the day most rev counters are more accurate than a speedo and most road bike speedo’s are set up for a standard bike any change away from that would create inaccuracies. The other problem with that is speedo must be tapped up so would be no use anyway.

What they do have at GP’s since not all bikes have speed limiters is speed signs like you get on road works. I believe the MMCC is looking at installing these as well.

There are plenty of other solutions if you think latterly. I am working on one at the moment that is a simple self-contained unit that could be fitted to any bike. However the lack of time to build and test means I probably won’t get it done for this year.

For most of the classics it won’t be a problem so I guess your on a 250 two stroke? Having said that we worked out the revs on the 350 Ducati I will be riding in the Junior classic and it’s getting towards 6000rpm. So you could still ride it with a reasonable margin of error.

As an idea how about suggesting that they put signs up on the return road during practice week will give people a chance to test speed limiters/calculations.

Only playing devil's advocate, as the two bikes I'm looking after shouldn't need to go in there - if they do we're already in big trouble I'm sure you can guess what breed they are

Smokey125, thats a great idea re putting up a sign on the return road during practice week.That way you could try different gears to get the correct speed. Would it be possible if say CARGO put it to the committee so we could at least have some idea before the big day.

You comments you made were perfectly valid superted and add to sensible constructive discussion.
I was perhaps a bit aggressive with my first post but I do get annoyed with people who appear to jump to conclusion without applying any common sense to there thinking. In today’s age of instant communication it's very easy for rumour to become fact in a day of two.
The MMCC have enough on there plate as it is trying to get things in place to deal with the speed limit without having people on the phone ranting about things that aren’t actually happening!

In reality I think very few of the bikes at the Manx will actually have the ability to run a speed limiter.

Shipley I thought of it whilst writing the post. Thinking about some of the points superteb made, I thought it would be a good way of seeing how accurate your calculations are before the race. I have emailed it to the MMCC just have to wait and see if they are able to implement it in any way. I will email it to one of the rider's representatives as well.