Ready to Race Finally

Hi Acrotel

My friend sold his Drainpipe to the National Motorcycle Museum. The frame & parts came out of the workshop. (back door)
I met at the Stafford show in 2004 when I was displaying the Drainpipe on the Norton Owners Club stand a gentleman who raced a Drainpipe with the Classic Racing Motorcycle Club, in the 80s. At the same show I met an Italian man who said he owns the Monza record braking bike.
Mr Robinson designed the frame he also had a hand in the MK3. If you sit on a Drainpipe you will not believe how narrow & comfortable it is. It is a Mk3 with no waist. Ray Pickrells favourite bike. (he signed it for the owner)
Copies were made & raced in Australia but I seem to remember Classic Racing saying they were not to original design ( were they scaled from photographs?)
The MK3 is good Acrotel but the MK4 is better. My Mk3 has clamp on front tubes where as the MK4 has a bolt in Ladder. The only other difference is the top tubes the Mk4 are wider. Keep ending up with tanks that don't fit!!!
If you do a search you will find lots on the Drainpipe.

Chris

I've never had the bolt-in ladder for my Mk3, I use a piece of chrome moly tube with as slight bend in it so it can stretch a bit as the motor shakes, so not snap at the welds . Bill Horsman used a Mk3 frame with Gerry Kooistra's G50, and said he could feel it twisting at the front. I've never felt that. My frame is stamped with CS Mk3 1966, and it is genuine not a copy. I don't doubt that a Mk4 is a better frame, however I try to keep my bike somewhere near authentic. Even though it has an 850 motor, that motor looks like the short stroke 750 so I live with it. Gus Kuhn used the Mk3 frame on his bikes. (Who else successfully raced a Seeley commando in the 60s ?) I try very hard to never use parts which are obviously Japanese. As far as the drainpipe frame is concerned, if it was raced pre-72 it fits into our period 4, which is essential if you want to race a commando in Australian historic racing. Moving into period 5 means the fast bikes you ride against are Katana engined XR69 Suzukis and the Irving Vincent. If your commando is not pre-72 (and mine has a date problem with the 850 motor) it is pointless building the bike.

Mike, I made the comment about the TZ250 Yamaha being faster than commandos. When I race, it is usually only at Winton Raceway. The circuit ids is 3km long and has 7 right hand bends and four left hand bends and it is fairly level and very safe. I was there yesterday watching a Moto Ride day. One pleasant young guy I was talking to was checking his lap times, concerned that others might have caught up to him. He was riding an R1 Yamaha, and his lap time was I minute 33 seconds. The lap records was held for many years by Sean Geronomi who rode a mid 80s TZ250 and clocked I minute 29 seconds. I think the record is now down around 1 minute 17 seconds, and held by a superbike. Strictly speaking my Seeley 850 is only eligible for period 5 where there are 70s TZ350s and TZ250s. I'm certain that if I was riding my Seeley 850 in period 5 and met myself riding an alcohol fuelled TZ250, I would look very stupid with the Seeley. Fortunately alcohol is banned in post 1972 historic bikes, however who is looking ?
Years ago I built a T250 Suzuki and ran it on alcohol. I never loved it even though I once trounced a TZ350G with it. I sold it and the new owner won 28 races and 5 championships with it. When I was racing back in 2004, that bike was at Winton in the hands of an old push bike rider. I got out of shape when I ran out of brakes on a left hander, and he slipped under me. I had to work really hard to get past him again. I watched a top rider on an RS125 Honda beat all the guys who were riding 600cc Yamahas around Winton in one particular race a few years ago.

Mike, I appreciate what you are doing with the BMW. If you are at a slight power or handling disadvantage and ride faster and smoother to compensate you will probably become a much better rider than many others, however take care. Many of us don't become better riders by riding bad bikes, we simply learn to stay upright better, and don't often get amongst the compulsive obsessives up front to learn how to lead.

I'd simply like to say in defence of BMWs that Gus Kuhn abandoned the Seeley Commando in favour of a standard framed BMW .

acotrel said:

Mike, I appreciate what you are doing with the BMW. If you are at a slight power or handling disadvantage and ride faster and smoother to compensate you will probably become a much better rider than many others, however take care. Many of us don't become better riders by riding bad bikes, we simply learn to stay upright better, and don't often get amongst the compulsive obsessives up front to learn how to lead.

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I'm curious, describe bad handling?, I can't say I've noticed it on the BMW , or the so called 'jacking effect' and "torque reaction " from the engine. :lol:

It gets worse...I have just bought another BMW racer.....

Mike is on the Commando. :wink:

72Combat said:

I'm curious, describe bad handling?, I can't say I've noticed it on the BMW , or the so called 'jacking effect' and "torque reaction " from the engine. :lol:

It gets worse...I have just bought another BMW racer.....

Mike is on the Commando. :wink:

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There is a jacking effect in which the rear drive makes the rear suspension extend under acceleration and squat under deceleration but I've never actually noticed it. There is a general consensus that you shouldn't shut off if the heads hit the ground because the squat effect might lift the front wheel. The answer of course is to be smooth and not go into corners too hot, squeeze on the power and it'll all be fine. But that's good technique for any bike.
With the torque reaction, revving the engine at standstill make the bike rock to the right, but it's not significant enough to affect the handling. I just use it to amuse passers - by when I'm warming the bike up.

As for lack of power.. do me a favour, it's a lot easier and cheaper to get a 40 year old BMW to chuck out 90 horsepower than a 40 year old Norton. You don't have to buy new crankcases for a start.

72Combat said:

I'm curious, describe bad handling?, I can't say I've noticed it on the BMW , or the so called 'jacking effect' and "torque reaction " from the engine. :lol:

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As just mentioned, if you are smooth, you won't have met any 'bad handling'.
That probably means your not riding at 100%, however.

I've done a few miles on BMs, road miles, and have once or twice met some interesting habits, shall we say.
Coming around a tight bend at a fair rate of knots, there was car lurking in my lane just around the corner.
I shut the throttle and braked, really hard - and the bike shuffled outwards a lane, nothing I could do about it.
Nothing coming the other way - luckily.

Another time, came hooting into a corner that tightened up, a lot.
Head touched the ground - might have been the crashbar, didn't think to inspect too closely at the time
Now, I knew that that was not good on a BM.
Opened the throttle, hard, and applied a little rear brake.
That trail braking into and out of tight corners is just something you keep in the back of your mind on shafties - I've also had a Guzzi.
(You have to be a LONG way over on a Guzzi to touch a head - but there are other bits !)

The answer I've heard to the 1st one is the top fork yoke is just a thin sheet steel item - not even 1/4" (or whatever that is in mm).
Apparently it needs to be something stronger if you are going to throw your bike around harder than average.
There are aftermarket ones.

You probably already have firmer than stock springs in the front forks. ?
Std is well on the soft side, for comfort.
And they don't last forever, either.

Interesting, I have both a race and road version of the R90/6 and they are like chalk and cheese as far as handling goes, horses for courses I suppose.

Handling is improved with racetech fork internals, linear springs matched for weight, rebuilt Konis, large tube swingarm, fork brace, billet triple clamp etc.
The road version is pretty stock but with twin disks, konis, progressive ( yuk) springs.
The racebike cost me less to build than a TT gearbox :lol: :lol:
I might ride it a bit harder now I have race Avons instead of BT45 road tyres.
If only I could bring myself to do 7500 in each gear on the Combat. :roll:

Well done John, great post, I will get some more pics of my race bike eventually.
Despite what others say, it doesn't really matter whether we are riding Bavarian Tractors or the Unapproachable Nortons (should read Approachable if I am riding one), as long as we are out there doing it on the road or on the race track.
Going to make a few subtle changes and unleash that extra 5 HP that I know is locked up in there!!!
Regards Mike

acotrel said:

(Who else successfully raced a Seeley commando in the 60s ?) .

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Nobody, it had to be an Atlas!

acotrel said:

If your commando is not pre-72 (and mine has a date problem with the 850 motor) it is pointless building the bike.

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The UK CRMC rules allow a 3 year run on for 'not substantially changed' specs, which allows my Oct '75 frame to be eligible, and has a dispensation for '850 engines' that however have to fit the capacity class, which means to run in F750 is has to be sleeved to 73mm or 77mm stroked at 80.4 to use 'standardish' readily available parts.

The Dunstall Drainpipe 750 Norton was originally a tuned Atlas engine, which was found to have too much power for the f/bed frame on British short circuits.
Ray Pickerell was the regular rider until Dunstall sold his shop to a relation, and quit motorcycles altogether, to go into the building trade.

Bernhard said:

The Dunstall Drainpipe 750 Norton was originally a tuned Atlas engine, which was found to have too much power for the f/bed frame on British short circuits.

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I have seen this comment before, and won't argue that Dunstall drew this conclusion, what seems odd is not only that others disagreed at the time, but some are racing Featherbed Commando's today with apparently higher power outputs than Dunstall was achieving....

Dunstall was involved with the early Rickman Metisse twins, by reputation a frame less flexible than the Seeley, anybody know why he forsook that for the Drainpipe?

Hi Steve

The easy answer is sit on one!!!

I did & I was sold. I did want to build one but was concerned that the club would not allow it. There was lots of "original" bike not replica talk at the time. It is a bike to be seen, I love my Mk3 but you just keep walking round looking at a Drainpipe. I am sure it would have sold on looks alone. I would have loved to have given it a run at Mallory it is just so tidy. Mind you Rays record says it all.
Chris

Chris, I can never understand the mentality in which the major or primary objective is to find a way to exclude bikes from historic racing. It would be interesting if one had money to burn, to challenge one of those club's eligibility decisions in court if it appeared vexatious. In Australia we even have one idiot in control who hates 'trick frames'. To my mind that is one of t he things that motorcycle road racing is about ! As far as I'm concerned the Drainpipe Norton is the same old garbage as a Seeley or a standard commando framed bike. If similar ever existed in the era and was raced , it should be permitted to race in our modern classic classes.
Bernhard, I believe the co-rider in the Youtube video 'race of the power bikes' was Ray Pickrell who was later killed ? Did he ride the Dunstall drainpipe before or after joining with Peter Williams in the Norton Team ?

Acotrel, you're getting very confused!

Ray Pickrell, was not the works JPN rider, he rode for the opposition (Triumph/BSA triples) He died a few years ago, but obviously not racing. He also raced a Seeley BSA3 for Boyers

Dave Croxford was Peter Williams team mate, and when I last saw him a few weeks ago he was fine.

replicas of one-off bikes are not allowed, but a replica of a "production" bike is allowed, so Seeley/Rob North etc replicas are allowed, but something like the Marsh 4, Jones etc would not be allowed.

Thanks for that, it was Dave Croxford I was thinking about. I still cannot date the drainpipe Norton. Does anyone have a record of when it was first raced ? Was it a late 60s bike ? I believe the Seeleys started mid 60s, mine is 1966 and it is a Mk3. It is useless thinking about building a bike with the drainpipe frame, if the idiots are going to can it. CRMC seem to have some smarts about them, if they allow a margin which helps guys to get racing. Was the drainpipe 'one off' ?

This is another picture of one of the Dunstall Drainpipe Nortons from an early (pre-72) version of Dunstall's tuning manual. There's no other info on it in the manual, but I don't think it's been posted to the list before, but apologies if it has. I offer it as another view of one of the original configurations. As Kenny (Homeslice) pointed out elsewhere on the forum, very few were made (4?), so it would never qualify as a production frame for most vintage race clubs.



Ken

We have the same rules that allow models that are unchanged to carry on thru, the example given is a Honda 750/4. At the end of the day I'm just enjoying doing a bit a classic racing, meeting people and having a laugh. Serious racing I leave to others.
Thanks to Mike I am now sorting thru my pile of parts..... :roll: