Klaus Enders Busch Chassis

[kface]

Well done to both of you on your opinions and as Steve said keeping it civil. Some older people should take note from you.How long will it before we get a comment on this from someone involved with the CRMC.Especially about the ride height comment and also I would be interested to hear their comments on the similarity to F2 width etc.

[sidecarracing]

very interesting topic this! And indeed, praise for not getting out of hand.
Please continue.
I will try to add something, please excuse my English sometimes.
The first question one should ask is what exactly is the meaning of a Classic Sidecar class with a racing (in this instance the CRMC) club?
In my eyes to recreate something from the past...but what exactly? Probably not the world championship rounds of the pre-73 period, because then the grid should have to be filled with lots of 500cc BMW Rennsports and we all know that is never going to happen.
So I think it should be to recreate the British Sidecar Championship of the pre-73 period, agree? Can anybody tell me which years had which capacity limit in that? was it 1000cc? or 1300cc? and if so, when did that change?
Before I continue I want to hear your opinions please.

[Kieran Clarke]

Hello John, the CRMC consists of three periods.
P1 - for production based air cooled twin cylinder 2 valve motorcycle engines. (750cc prodcution twins)
P2 - for twin cylinder engine specials and multi cylinder engines (750cc specials and multi's)
P3 - for multi valve multi cylinder engines over 750cc up to 1300cc (Also Car engines from period) also Honda 750 single overhead cam restricted to 836cc.

[RARING TO GO]

Kieran, question to you, a member of the CRMC; Why are Konig engines banned while TTi gearboxes, three piece wheels and programmable ignitions are allowed?

[jkr46]

Keiren,I think you will find a sheet steel chassis is lighter than a tube chassis,and also probably stiffer.
That is why Colin Chapman(LOTUS)designed the Lotus 25 as a sheet steel chassis,and the customer 24 in tube frame in the same year.
I suspect the rule on tubular chassis construction was made around 1980,when the newest elligible outfits were 8 years old,by people who were around at the time.
Classic racing is supposed to represent a period in time upto 1972,therefore the majority of club,and national level outfits would have been tubular construction.
Only innovaters,such as Busch,and Kurth etc would have built sheet steel chassis,they did this as they thought that they would be superior to the tubular chassis.
IF,this type of construction was eligible,and IF there was a clear performance advantage,then everyone on the grid would want one.
Then you would be in the same situation as you are now,a gridfull of similar bikes,and everyone has spent a fortune trying to gain a competitive advantage.
Why do you think there is now so many BMWs on the classic grid?and very few Triumph and BSA twins?Which were the mainstay of sidecar racing in the period the club is supposed to represent?
When I first started,I briefly raced with the CRMC,and on the grid at most meetings you had BMWs,BSAs,Triumphs twin and triples,Welakes(Nourishs),Nortons,Yamaha XSs, the SAAB and of course IMPs.
From a machinery perspective they were all reasonably competitive,and obviously provided great variety for the spectator.
The triples were the thing to have,then the Weslake took over,then Imps now BMWs.
When one type of machine/engine starts winning everybody want one,the same as modern racing.
So for Classic racing,a line has to be drawn somewhere,and for chassis it was drawn at tubular,and personally I think that its a good rule.

This is a very well thought out reply and I agree 100%.

[jkr46]

Hello Jason, what makes you think everyone will want to have a chassis like the one dieter built? There is a lot more material put into it compared to a tubular chassis so they will be much heavier. From all the pictures, videos etc i have seen from before 1972 all the outfits on the gird look completely different and they are all unique. We are now in 2015 and a good percentage of the outfits on the grid are built by mike richards and the majority of them look the same or if not identical. I am not saying mike is taking over the grid but i do think that most of the classic outfits look the very similar except the likes of john perkins right hand chair chassis. It would look better if there was a different type of 'classic' sidecar on the CRMC grid and if the majority of the people who own a tubular Windle or MRE chassis wanted a sheet steel one they would usually sell their current outfit and someone else would then ride it so it will still be out there on the grid. I wonder who decides on these rules for the sidecars and where they get the information from to decide on what happened where and when because as far as i am concerned, if you wasn't there in 1972 you shouldn't decide?

Mogli

I would strongly disagree most purpose built chassis's (not converted motorbikes) I've seen from period photo's and video look very similar.

If you put a MRE, Windle, Busch tubular and a bellas chassis in a line they are all very similar does this not tell you something?! Their designs are based on the majority of what was around in the day.

[jkr46]

Now then Tony
The surface area of the material in a sheet steel chassis is greater than a tubular chassis and the wall thickness is near enough the same depending on the chassis builders design/idea so this would make the sheet steel one heavier. The sheet steel construction from the head would not have the ability to flex as much as the tubular chassis so the sheet steel one wont handle quite as well. People may say they will buy one if they have an advantage but you will find the majority of the people who race sidecars as a hobby may not be able to buy one, but if they do buy one, their old bike will still be raced by the person who buy's it? Then you have to ask who is going to start making them? What if they make them incorrectly? Would you buy one? You will also find in the CRMC there are a lot of BMW's however the IMP's are still winning and breaking lap records so why doesn't everyone have an IMP engine? If a construction of a chassis from the period cannot be used, how come you can use ride height adjusters on a 'Classic'? That is a perfect example of a modern advantage but only Mike uses them on his classis chassis so you cannot say everyone will use the same competitive advantage. Yes only certain superior people built sheet steel chassis up to 1972 but because they had fantastic ideas and creation that were still in the period. There will be no advantage building a chassis out of sheet steel other than it will look a lot nicer and it will add something different to the grid.

What do you think to the tyre situation Tony? Do you think the Yoko's should be allowed or do you disagree?

Mogli

In my opinion your wrong you wouldn't need anywhere near the same thickness for a sheet steel chassis as a tubular one.

I'm not sure where your idea comes from that having your steering head flex more improves your handling? Or am I miss reading this?

[666]

very interesting topic this! And indeed, praise for not getting out of hand.
Please continue.
I will try to add something, please excuse my English sometimes.
The first question one should ask is what exactly is the meaning of a Classic Sidecar class with a racing (in this instance the CRMC) club?
In my eyes to recreate something from the past...but what exactly? Probably not the world championship rounds of the pre-73 period, because then the grid should have to be filled with lots of 500cc BMW Rennsports and we all know that is never going to happen.
So I think it should be to recreate the British Sidecar Championship of the pre-73 period, agree? Can anybody tell me which years had which capacity limit in that? was it 1000cc? or 1300cc? and if so, when did that change?
Before I continue I want to hear your opinions please.

John, Capacity limit's before before 1972 were different at different meetings, some were 1000cc others were 1300cc also there was unlimited. I can only go back to 1964.

[jkr46]

Colin Chapman went bust a while ago. Also this is a sidecar racing forum.

Weslake? Yes, Alister Lewis. Other engines Yes, Moto Guzzi and Norton. Why would a 750 BMW finish in front of a 1000 BMW in the same race, although John Perkins finished second on his 16" 750. Kevin Hunt wins plenty of times on his 998 IMP which is an original period chassis with distributor ignition set up and he won the 2014 CRMC championship. Our bike which Neil passengered on was an original 1969 Windrick IMP chassis and that went very well as you know and set many lap records and finished second in two championships and now Stuart Applegate has it. John Perkins sold his bike and Damien Perilleux races it and was winning in CRMC last year. Nick Houghton sold his Weslake to a chap who currently races it. Chris Latham sold his Windle BMW and Paul Owen races it. Geoff and Ruth hands had a 998 Windle IMP and that still has the lap record at the Pre TT even though Vince Biggs has raced there on Busch BMW, Nick Houghton on Windle BMW and Eddy on his IMP and BMW also many others such as Wally Saunders, Colin Lewis, Stuart Digby? Damien bought Geoff's 998 IMP and still managed to beat BMW's, so did Eddy on his imp, and now Kevin Hunt can easily beat a BMW on his 998 IMP and so can Clint Faulkner on his 1200 Imp. Has that answered your questions? You do get to know this information when you are a member of the CRMC and race in the club.

How come you have an opinion on chassis and engines in the CRMC but you don't want to give your opinion on tyres?

Mogli

There are lots of things wrong in this post.

The question was did any weslakes win last yr, the answer is no, Alastair Lewis didn't race at any crmc meets last yr. That said a good weslake has the potential to win against any crmc eligible engine.

Kevin hunt was on a 1200cc imp last yr the only time he used his old engine was when the 1200 had issues which wasn't at all until donington and I'm sure even his old engine is around 1020cc now.

His chassis isn't an original from the day chassis, jan Herbert built it when he wanted to improve his Windle. Since then mike Richards has done work on it and kev has improved some bits aswel!

If your old imp was a windrick why was it always entered as a bellas imp?

[lang]

It is mentioned in this post that the Colin Chapman Lotus 25 was of sheet steel construction, it was a monocoque of L72 aluminium construction.
The advantages of this type of construction are, structurally stronger, lower and lighter, greater torsional rigidity.
The main reason for having more torsional rigidity is to allow more supple suspension settings to be used, a distinct advantage in some situations.
Some of these advantages will not apply to a sidecar chassis built from sheet steel.
PS Jaguar used a monocoque aluminium construction on the D type race car long before Colin Chapmans Lotus 25.
As regarding eligability for classic sidecar racing, there is no doubt, several sheet steel chassis were built and used before 1972.

[Kieran Clarke]

Hello Michel, i don't know answer to that, Howard Langham will tell you because he had that problem.
Hello Jason, Tony didn't ask the question what engine one in the CRMC his question was did a .... win last year. An sorry my understanding of Kevin's bike must have been incorrect. Ed bought our old IMP a long time ago, Ed spoke to Windle about it and Windle identified it. Ed took it to Rod Bellas and he Cleaned it up and replaced a few tubes that had a lot of rust build up on them. After Rod did all the work on it, for his thanks we entered it as a Windle Bellas IMP. The bike still has the original Rubber donut and Mini car dampers on it.

I spoke to Rod Bellas today and he would be interested in building a sheet steel chassis. He also said that a circumference of a 28mm tube is roughly 88m and a 32mm tube is 100.5mm. The bottom rails on a sheet steel chassis wold be about 70mm x 30mm giving 200mm. The sheet steel chassis would have 1.2mm wall. Tubes would be 1.6mm. There is more sheet steel than there is tube from the head so how would the sheet steel weigh less?

A sheet steel construction would make the bike very rigid. A tubular construction would allow slightly more flexibility. If you watch a F2 Baker or Windle in the Isle of Man they handle better over the bumps. If you watch an LCR you can see they are more rigid. My thoughts anyway.

[tonybsa2008]

Howard,I stand corrected on the Lotus 25.
Kieren Colin Chapman did not go bust,he died of a heart attack.
I also aggree the Konigs should be allowed in their eligibility has been proven.what are you all frightend of?
The tyre question is a seperate thread,and my opinion,rightly or wrongly is in there.
This thread has,actually produced some very informative and usefull information.

[kface]

I heard quite sometime ago on the old grapevine that Howard was told he could race at the CRMC, but on a probation basis that no doubt would be reviewed if he started winning.Sounds about right,hopefully if I'm wrong Howard will say.As you say Tony let them in and anything else that raced in the day.Get some variation and interesting outfits on the grid please!!Perhaps they could ask the Vintage Club for some ideas.

[kew]

As someone who was there in 1972 and before I hope that I am allowed to comment.
I thought that classic racing was about looking through the rose coloured glasses and racing bikes from the past, in this case pre 1972 for 4 strokes and pre 1967 for 2 strokes. There is an allowance for new chassis to be used because old chassis may now be unsafe but surely these new frames should be copies of pre '72 chassis and not to modern dimensions, I also believe that they should be of tubular construction.
I can't help thinking that some classic competitors are spending very large amounts of money to buy success to be a big fish in a small pond. The £12000 BMW's
and the 1200cc imps are not classic bikes, I know because I was there and my BSA was competitive then, it wouldn't be now.
As regards the Konig engine, it was the first of the 2 strokes that eventually sounded the death knell of reasonable cost racing, they should not be allowed into classic racing under any circumstances, they have a place in post classic.
I also don't believe that development and classic should be used in the same sentence.

[sidecarracing]

As someone who was there in 1972 and before I hope that I am allowed to comment.
I thought that classic racing was about looking through the rose coloured glasses and racing bikes from the past, in this case pre 1972 for 4 strokes and pre 1967 for 2 strokes. There is an allowance for new chassis to be used because old chassis may now be unsafe but surely these new frames should be copies of pre '72 chassis and not to modern dimensions, I also believe that they should be of tubular construction.
I can't help thinking that some classic competitors are spending very large amounts of money to buy success to be a big fish in a small pond. The £12000 BMW's
and the 1200cc imps are not classic bikes, I know because I was there and my BSA was competitive then, it wouldn't be now.
As regards the Konig engine, it was the first of the 2 strokes that eventually sounded the death knell of reasonable cost racing, they should not be allowed into classic racing under any circumstances, they have a place in post classic.
I also don't believe that development and classic should be used in the same sentence.

what else is there to say? 100% spot on!