Reliability in racing

Reliability - In answer to John Bass's post on the old web site yesterday I think Bantams are more reliable because ignitions are a lot more user friendly than old Kettering system - battery and coil set up just pop on your pvl,motoplat or whatever and leave it alone. The "state of the art"ignitions can be a problem because the owner can fiddle and change things?
Myself and PJ know everything about our bikes and milage everything so you change things at a safe milage ... say a primary chain 400 miles , big end 1000,piston 350,ring 200 and on and on... so its all about not expecting too much from your parts ?
Talking of primary chains can i order 2 Robbie please
Mike

Keep at it Alan -- don't let the electrons and old ions get you down!
Hey Mike!
You've got to be right! Our (Icarus 1) spark voltage was probably about 6,500v at best and when the battery was getting feeble about 5,500v so things could get dodgy around the plug when the combustion was getting to be at optimum. Icarus 1 frequently seized as I was passing someone which suggests it was going at its best just before the piston got too large...
A Robert Bosch expert gave me a fantastic spark plug that was used for two seasons without cleaning (that was because he said 'You never need to clean this blutty sparking plug...'). Before that with Lodge... I had to start up with a soft plug before changing to hard... and always cleaning them. Latest ignition systems give very high voltage at the plug which aids reliability (as you said)-- my R.Bosch book says 15000volts for transitorised ignition! That's probably out of date by now.
Seems you keep things well recorded -- I tried to... With the 250 I kept better records because Andy Boyle put a lot more money into the bike than seemed justified with me driving...
Clutches were the greatest difficulty with both Bantams. After suffering the Albion clutch on the 250 for half a season Andy got me a Greeves Griffon clutch (for the 250) and that was 'Sweetness and Light... --
Oh nostalgia -- Shakespeare said it was "... the whore of memory..."
_-- he was right!
Take care! John.

PS -- or is it p*ss...!
I thought someone would jump on what I said about ignition and tell me that it ain't only low voltage at the plug that can give bother. Low voltage does contribute... but CB irregularities, at high speeds, are the main cause.
An exercise done (by a UK Auto manufacturer, in the '60s) to establish the limitation of mechanical contact-breaker's timing accuracy showed that above 6,000rpm (100revs/sec) the start of spark (timing) varied considerably and increased in its inaccuracy the greater the speed increase went above a 100breaks/sec. Hence the possibilty of too much advance/retard at a WOT (wide-open throttle) time of optimum combustion could have rapid overheating to initiate a piston seizure.
That happening with inaudible detonation -- no 'pinking' warning...! We knew this, of course, but lived with it...
Icarus 2 had a 'transistorized system' and still (frequently) seized which
which I blamed more on my port timing experiments with max revs at 11,000rpm plus... (Pistons used to stretch as well ...). No dyno available in those days...
All the best,
JayBee.

Whiskey was created so that the Irish would not conquer the world!

I remember the last race of the year at Lydden 77, as I took the flag to win the race, my points fell apart and the winner had to push back to the paddock I fitted a Lumenition kit for 78, I believe it's original destination should have been a Ford Transit but it worked very well in conjunction with the Gardner carb I purchased (remember them?).

Yeah Mick!
Simple.
But sometimes that simplicity was the Achilles heel of the total reliability of the machine. With Andy's 250 the mixture had to be rich otherwise a hole would appear in the piston crown. My opinion is that a reed valve is necessary with a Gardner... Andy has the same on his GP5(that's in its development throes just now with John or Joe Butcher in the saddle...) and agrees with me but the casting change to the crankcase holds him back -- plus to legally replicate the ABS he might be breaking rules in fitting a reed valve -- I think!?
Of course, the ABS/GP5 having the flywheel-peripheral valve type of intake system complicates this issue. With this arrangement there was so much 'blow-back' from the Gardner carb that I had to put a new lot of absorpent foam under the crankcase each time out otherwise I'd be a menace in terms of oil on the track.
A Gardner expert did some 'plug chops', with me, at Brands on a Wednesday to determine the NEW needle required. Wow! was the ABS really flying then! On the following Sunday the ABS was so quick -- but only for one and a bit laps -- it was noticed. Really motoring on the second lap of practice in the OLD Norwich Straight (very long and boring...!) with the passing of Japanese bikes an unbelieveable feeling of wonder & delight. Then -- tink-tink! -- the back wheel locked before I could decouple the clutch. It was another day gone... Those who'd noticed its acceleration were obviously breathing sighs of relief at the demise of the ABS.
The hole in the middle of the piston crown is the size of an old farthing with the surrounding area sunken like a funnel. I say IS because that piston is sitting on my comptuer--a metre away from this keyboard.
Point is the Sunday ambient conditions were not much different from 4 days earlier so why should such a disaster happen? It was definitely weak mixture that caused the seizure. It suggested that the Gardner might be too simple...?
Hmmmm! -- I wonder what the difference is: in the height above sea-level of Snetterton to Brands...? Only small I should think?
Wal Phillips, early days Speedway rider, developed his own Fuel Injector
that was somewhat akin to the later Gardner except that it was more simple. Of course, with those (mostly) JAP engines on dope the carburation
was just a large hole...
Thanks for asking the question. I hope we are not hogging this site too much!?
Cheers! JayBee.

John/Mike
I understand the design of pistons has progressed a long way, and they are on average considerably better in materials as well. As bantam riders/home shed engineers we tend to use any piston that will fit, both in terms of size and cost! this creates some mismatchs for instance a piston designed for a watercooled barrel (low taper) being run in an air cooled barrel (needs high taper), the consequences are likely seizure, or run greater clearances to avoid it, possibly richer than ideal mix as well to keep the temperatures down. Thinking back this will have accounted for many of the siezure problems that I encountered in the 70s. Best thing to do is be safe on the clearances and work careful, to get towards your ideal.
Carburation has moved on a lot, I used the Gardner very successfully, but note the tendancy to run lean on extended open throttle, this is corrected by the powerjets we now have. So saying even modern carbs will tend to lean out after long periods of open throttle, just look at the unreliable start to last season I had! this was caused by just that tendancy, but it is not easy to see straight away, and I took a few meetings to get over the problem with the addition of the powerjet.
All these small things add up to improved reliability, but I agree with Mike and say the same, dont expect too much from the main running gear and change parts at sensible intervals. See Mikes mileages....

Cheers,
alan

Thanks Alan!
It might well have been the way we started out, with the policy we stuck to, that kept Icarus-1 as a bit of an Also-Ran:-- "Racing on the cheap" as Roy Bacon's article decreed. We had the cash but we never splashed out except for CR gears and tyres (four seasons!). Just look at the picture of IckyOne --- you can see it is bare-bones Bantam yet on that particular day at Cadwell it was winning...
Later we went daft and bought a fairing...
There were three of us involved -- all auto engineers and serving Henry Ford at Dunton -- so we should have had a championship winner -- it was that we made the 1st Bantam Racer for about 60pounds and I made Icarus-2 for 40 quid.
Derek was our engine man (he was supervisor of Ford diesel engine development), Les(worked for Ford as a piston specialist) acted as our turner and machinist (and bits finder -- engine found in a field among other fantastic bits...) and I was chassis constructor(Simms fuel injection expert & Ford Test Engr. later...). The frame was Cad-plated at Leyland North Works whilst I worked for Simms.
Our little team was a bit like Ford's "Component Development Engineer" system -- it was not too fruitful in terms of producing the very best -- which didn't work too well for Henry also. But Icarus-1, at 60 quid, gave me a lot of fun in Inter races for 4 seasons.
With Icarus-2, I went it alone but my 'Watershed' (I got an offer from a New York employment agency for the job in Canada) came too soon to get the Icarus-2's development sorted and I had Andy Boyle's 250 to race which cut back on the spare time for Bantam tuning. Spare time -- there was never enough. With Simms I was at Leyland -- 200miles from home --
for full-weeks at a time.
It was, I think, that we didn't take it seriously enough. Yet I look back on it -- all these decades later and say I wouldn't have missed it for all the 'hot-dinners' (read my lips!) in the world.
During the early days of development of a new (Air-cooled) Deutz diesel engine in Montreal I personally relieved the high spots (to the amazement of onlooking engineers) on the pistons of the first experimental engine we had on its intial dyno tests. Later that profile was fed into a Carl Schmidt piston making machine which machined the 'double ovality', 'taper' and 'barrel' shape...
Many moons later I went to China, Africa, Yemen and Colombia (for the German government) talking about engine development and actually persuaded a Chinese company into 'Squeeze-casting' their pistons...
So what went wrong with our engine tuning?
I'd say nothing really. I made a fuss here about piston seizures (mostly 'nip-ups' at Brands 'running in'...) and burnt-out clutches possibly to excuse my lousy riding and we knew there were more exotic pistons with better materials available (even at that time) -- it was that we kept it CHEAP!
We made a Bantam Racer (Icarus-1) for half of what the Senior, fast ones were going-for and I learnt a bit about how to road race (ooh my shoulder and knee do give me jipp...!).
For a young lad -- half my age, of then -- it would have meant a good introduction -- really cheap for him -- into the learning of motorcycle racing. But we couldn't find one -- so I volunteered to be test-rider and then got bitten...
It could still be that way -- I guess. Relatively the 175 Class Bantam is
a good LOW-COST machine... Or am I spouting drivel again?
It could be, if the likes of Tom Miller are still out there -- be the perpetuation of Bantam Racing... I hope so.
Stay cool and keep well,
Aye! JayBee.

I wonder if there ought -- perhaps -- be a 'MoS':-- 'Moment of Sympathy...' published somewhere for the rider with the most 'dnf s' against his name in the 2006 Results.

Mick has none: his record is 20 finishes out of 20 starts. M. Potter and P.Tibbitts have one 'dnf ' each but Peter has 4 'n s'.
Alan Brown has 5 'dnf s' and one 'dns '. Phil Betty has a 20 out of 20... a reliability record equating Mick Powel's.
Carl Coombs -- 3 of each: 'dnf s' & 'dns s' -- 14finishes...
Ian Scutt has 6 'dnf s' and 2'na s'(whatever they are...?).
I reckon the MoS should be for Ian -- but he did become a Dad so we shouldn't feel too sorry.

Last word -- I promise!
Aye!

John, Snetterton is almost at sea level, no other circuit we used was of such a low altitude, and combined with the much longer straight, meant seizure was inevitable with a set up which was good for Brands.

(My 4 dns' last year were due to being on Holiday)

PJ

Thank you Peter!
Why dinn' you tell me then! Before I went to Snetterton. Oh no -- of course you couldn't -- in them days you was a tripping over your hair trying to fly your model aeroplanes... Cor! Weren't it a lovely mop in those days?!

Really showed my ignorance there didn't I! My excuse is that I was with a Gardner carb 'expert' at Brands when we did the 'plug-chops' and he set the needle - he said was SUITABLE for Snetterton. I think Andy once said you could run the ABS without a needle... Like a track carb when using dope! It certainly gulped its fuel and at times was really quick. In fact, I think faster than John Senior's Greeves Silverstone. Point, I think, was that the Gardner was just a bit too senistive to ambient changes and as Alan implied an auxiliary jet is essential...
Actually though, I do think we didn't do too bad with the 250 ABS when compared with Andy's 1st season, 2006, with the GP5(replica of ABS, I think). He was on the phone yesterday complaining of inertia -- his. Maybe if he reads this he'll get off his fat .... and get the GP5 ready for the March meeting.
Spoke to Slick on the phone today and he told he fell on his head yesterday during an Enduro in the IoM. I said it is bloody bonkers to race motorcycles and his answer was that it was fun. FUN!
Really! Is that true?
Clare Aldridge, Wobbleyman's widow, is well pleased about the trophy. Apparently she had a call from George Harris recently.
.....HAS ANYBODY GOT George's phone, e-Mail or other contact number, please?
Take care and keep well, John-Boy.

Hi Mick (and Alan),
Bill would like to hear from you. Apparently he is having bother with getting accepted on this site -- I did too. Only by putting in my age did it állow me to log on. All very strange.
Anyway here is Bill's e-Mail:-
billlawrence@ozemaail.com.au

All the best! John-Boy(been taking V-tablets!)

Mick and Alan,
There are 3 'l's in Bill's e-mail address and not two 'a's in ozemail
billlawrence@ozemail.com.au
Sorry, JayBee.

Cheers John, i'll get an Email off to Bill, it'll be great to get in touch again after all these years.

john,

From 1970's memory Chipping Sodbury 312816

Code is now 01454, but BT does not show any G Harris with this number.

Pete