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brianbuck

Rev Limiters

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9 minutes ago, OveFundinFan said:

Watched on you tube yesterday England v Sweden at Sheffield 1973, a young Peter Collins against Anders Michanek on 2 valve Jawas. It was a brilliant race, and they certainly would be restricted on revs compared to today’s rocket ships, the costs would be cheaper, good market for used equipment to be sold to newcomers/learners that are rideable, and probably benefits in area of track preparation, and as bike costs fall so could entry fees for spectators.

Why cant speedway just go to modern day 2 valve bikes, times maybe slower but racing just as exciting.

Because all riders would then have to spend thousands on buying new cyliner heads for their engines!

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All they would do is put two valve heads on very short stroke engines and with a bit of valve and porting work be very close to where we are now within days.

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22 hours ago, OveFundinFan said:

They spending thousands now on engine tuning how many times per season?

You think that top riders will spend any less? Two valve engines aren't going to change things. Or do you think that everyone will buy 1970s Jawas?

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1 hour ago, *JJ said:

You think that top riders will spend any less? Two valve engines aren't going to change things. Or do you think that everyone will buy 1970s Jawas?

I did say MODERN 2 valve engines. What was wrong in speedway in the 1970's, after the outdated JAP engine and before the more expensive 4 valvers?

So you tell me, how are costs going to be reduced so that speedway is a cheaper sport to run? Or are we just going to watch speedway in uk continue to die a slow death. 

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On 1/21/2019 at 11:13 AM, *JJ said:

Because all riders would then have to spend thousands on buying new cyliner heads for their engines!

or alternatively ,chop the one of the valve rockers off so that only one inlet and one exhaust works

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I think it's a bit of a myth that the old engines were more reliable for starters. Even good Grass track riders would grind the valves and check the motors on a JAP every other meeting (some every meeting). I don't know about the Speedway boys but I remember the 2v Jawa was a big step up reliability wise. I used to strip my 2v more often than I did my sons 4v Jawa's although a lot of that was because I wasn't riding very often so had time to mess about. I have been told the most reliable engines between services were the 897 & especially the 898 4v Jawa's which I've been told would run all season at a good level with one rebuild.

Even in the good old days riders like Briggs and Co would hire an engine from one of the top tuners for the big meetings for a fee plus a bonus if they did well and it could work out very expensive but worth it to the rider in terms of future income. The best riders always had the fastest engines and spent good money on having them tuned.

Personally I think that getting back to long stroke engines with a rev limiter set to work at just below their normal ceiling would be a good start. Very simple to measure engine stroke and rev limiters so would be easy to police. Not sure it would reduce costs by a vast amount but would in my opinion give a bike that was safer to ride.

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15 minutes ago, Vince said:

I think it's a bit of a myth that the old engines were more reliable for starters. Even good Grass track riders would grind the valves and check the motors on a JAP every other meeting (some every meeting). I don't know about the Speedway boys but I remember the 2v Jawa was a big step up reliability wise. I used to strip my 2v more often than I did my sons 4v Jawa's although a lot of that was because I wasn't riding very often so had time to mess about. I have been told the most reliable engines between services were the 897 & especially the 898 4v Jawa's which I've been told would run all season at a good level with one rebuild.

Even in the good old days riders like Briggs and Co would hire an engine from one of the top tuners for the big meetings for a fee plus a bonus if they did well and it could work out very expensive but worth it to the rider in terms of future income. The best riders always had the fastest engines and spent good money on having them tuned.

Personally I think that getting back to long stroke engines with a rev limiter set to work at just below their normal ceiling would be a good start. Very simple to measure engine stroke and rev limiters so would be easy to police. Not sure it would reduce costs by a vast amount but would in my opinion give a bike that was safer to ride.

as far as I'm aware  titanium valves  cannot be  reground , once the stems have stretched that's the end of them ,single use at 3 times the cost  , titanium conrods allow more revs becuase they are light once again 3 times the cost for  minimal gain , titanium rockers lighter less mechanical weight  more revs at 3 times the cost . so we have these peter  johns titanium engines that weigh the same as a bag of crisps , that cost a fortune  muted by a rev limiter , IMHO  a dangerous expensive and uneccesary piece of equipment , forced on speedway by a govenring body ,that knows little or nothing about speedway and cares even less ,as long as it's sure it's bleeding every last penny out of it . rather like the E.U. is doing to the UK

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6 minutes ago, adonis said:

...forced on speedway by a govenring body ,that knows little or nothing about speedway and cares even less ,as long as it's sure it's bleeding every last penny out of it . rather like the E.U. is doing to the UK 

These are the people you claim have little or nothing. It's an updated list since I know Seppänen started o n Jan 1st.

Armando CASTAGNA, DIRECTOR
Lydia ROBIN, Coordinator
MEMBERS
Thierry BOUIN, FFM
Christian FROSCHAUER, DMSB
Svend JACOBSEN, DMU
Petr MORAVEC, ACCR
Tony OLSSON, SVEMO
Pavel ONDRASIK, ACCR
Darija PRSA, HMS
Jouni SEPPANEN, SML
Jan STAECHMANN, DMU
Anthony STEELE, ACU
Wojciech STEPNIEWSKI, PZM
Piotr SZYMANSKI, PZM
Oleg ZAKHAROV, AMFK
 

I'm not a fan, but there are people that know about speedway...

 

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1 hour ago, f-s-p said:

These are the people you claim have little or nothing. It's an updated list since I know Seppänen started o n Jan 1st.

Armando CASTAGNA, DIRECTOR
Lydia ROBIN, Coordinator
MEMBERS
Thierry BOUIN, FFM
Christian FROSCHAUER, DMSB
Svend JACOBSEN, DMU
Petr MORAVEC, ACCR
Tony OLSSON, SVEMO
Pavel ONDRASIK, ACCR
Darija PRSA, HMS
Jouni SEPPANEN, SML
Jan STAECHMANN, DMU
Anthony STEELE, ACU
Wojciech STEPNIEWSKI, PZM
Piotr SZYMANSKI, PZM
Oleg ZAKHAROV, AMFK
 

I'm not a fan, but there are people that know about speedway...

 

Plus Jim McMillan and Kelvin Tatum.

Edited by Tsunami

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Makes no difference how many sppedway names are on there , if the whole organisiation treats the sport  like something it trod in ...

 

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26 minutes ago, Tsunami said:

Plus Jim McMillan and Kelvin Tatum.

What do they do? 

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2 minutes ago, f-s-p said:

What do they do? 

Jim is the BSPA expert guy on mechanical issues, whilst Kelvin is an ardent ex rider come technical guy who fronts the PL TV average. Kelvin is highly regarded for his technical views and has already endorsed their use in our leagues.  He's probably already tested them.

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3 minutes ago, Tsunami said:

Jim is the BSPA expert guy on mechanical issues, whilst Kelvin is an ardent ex rider come technical guy who fronts the PL TV average. Kelvin is highly regarded for his technical views and has already endorsed their use in our leagues.  He's probably already tested them.

Ok, but they are not in the FIM CCP which is the name list I copypasted. Anyway, like we remember from GTR thread about two years ago we knew the limiters were coming. At basically no extra cost.

still, I’m with Vince that ban shortstrokes and go back a few steps on that route.

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11 minutes ago, Tsunami said:

Jim is the BSPA expert guy on mechanical issues, whilst Kelvin is an ardent ex rider come technical guy who fronts the PL TV average. Kelvin is highly regarded for his technical views and has already endorsed their use in our leagues.  He's probably already tested them.

FOR many years Jim was the FIM's chief machine examiner and Kelvin is still heavily involved with the technical side of the sport and has a sophisticated workshop complete with a dyno.

Also, the FIM and BSI are working closely together to try and find ways to reduce the cost of speedway to riders including a new engine that would cost around 3,000 euros, about 2,000 less than the current models, and would also be much cheaper to run.

Edited by PHILIPRISING
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