Looking through my archive I came across a folder I had carefully filed years back...it contained transcriptions in my hand writing of interviews I had done with champion Australian riders of the past....
Don Bain, Dave Jenkins, Sid Willis to name some....Velocette riders of course - my passion....
I've started to retype them with the intention of featuring them, with photographs to assist in my blog.
Now those of you who are in far away places may be put off by this, but pause a second and reflect that they could and do, contain tuning information and other such "small gems" in the text that can still be useful today...
Read on....
Left click on the images to enlarge.....
The text is as written in longhand by DQ, transcribed from audio tapes made of the interview with notes.
No comments or attempt to edit what was then written.
My occasional comments are in brackets and in italics...
Obviously his comments are sometimes quite critical and scathing of others and the Velocette factory special engines sent out.
But then top riders all had an opinion of themselves.
Mk7 738 Dave Jenkins
Mk.7 737 Ron Kessing…..about 1938
KTT and 500 Mussett Velo brakes identical.
Reduced KTT rocker weights from approx. 5¼oz. to 3¾ or 3 5/8oz allowed revs to 8000 with no breakages.
Rockers break at the cam end.
Factory made heavier, “spring breaker” rockers – this was the wrong approach according to DJ.
He also said the balance factor was wrong on the KTT ex works, over 100% and it was rough over 6900rpm.
He set up similar to Mk.7
Then was so smooth a 2/- piece was safe on the tank at 8000rpm!
1948, P & R’s got KTT1030, ex Fred Frith which went to D. Jenkins.
(according to Hedley Cox, KTT race mechanic, notes, 1030 was renumbered, originally KTT956, ex Ken Bills, 1031 was also renumbered previously being KTT468/8. DQ)
KTT1031 ex Bob Foster which went to Les Slaughter.
1030 had a TT BTH magneto and 1031 had a Lucas magneto. D.J took 1030 because of the BTH magneto.
These were “hopeless” when they arrived, only 98mph on petrol at
This was a section of road on the southern outskirts of
Had a 1 5/32” Amal R.N fitted.
Contrary to opinion these were a good carb. and could be made to run on alcohol fuel. Special needles were made up out of spokes! Spokes were 0.100” thick.
Methanol no good, engines ran too cold, he used a Vacuum mix. 70% Ethanol 15% Petrol and 15% Benzol.
760 main jet, thin needle, 109 needle jet. 800 main jet too rich.
Ray Madden had a Mk.8.
Brian Lemon bought KTT1030 in the early 1950’s. he used Castrol R despite D.J’s objection and as a result ruined cams. D.J would not sell him a replacement set of “D.J” cams- so it never “went” again.
D.J used Castrol XXL rather than Castrol R because XXL thinned out better in the relatively short races in
He say XXL gave 3 BHP more than on Castrol R!
He used a different radius on the rockers.
K17/8 cam better of the two.
K17/11 more lift than K17/8, 0.020” more.
K17/11 too steep a closing ramp, valve left “up in the air”, “D.J” cams more gentle closing, big lift.
He used about 1/16” bigger inlet valve. Missed gear, valves touch badly. Therefore attention to gearbox for gear changes a must.
He polished the edge of the cam plate. This reduces sticking by the pawl. The “V” he rounds entry and exit into the notch so it tends to pull in.
The selector dog between 3rd and 2nd he machines off every second dog, more backlash on “shutting off” but goes into gear easier and positively. Machines off every second top gear dog for the same reason.
Use of the “phantom” gear for ½ tooth differences.
The “phantom” gear utilises the fact that there is 44 teeth between the gears on both shafts in a Velocette gearbox, so for the top gear set often 18 teeth and 26 teeth on a KTT, having a special 27 tooth gear made on the same pitch circle diameter as the 26 tooth gear results in a ½ tooth difference than going to a 17 tooth, 27 tooth setup, enabling better gearing for some racing circuits. DQ.
Engine 23 teeth, clutch 44 teeth gearbox 25 teeth rear 47-48 teeth with 8000rpm at
Use of MSS two piece crank pin, ground for 16 rollers, he made his own big end con rod journal.
Flywheels made up, as original ones cracked.
The shafts were found to be annealed.
D.J’s KTT1030 4800-5200 onto the megaphone.
His had the extra oil pump. Bottom bevel box fills, drains to sump on the start line and so often oils up motor when you start, blows smoke.
I returned the following week for a longer interview......
DQ’s interview with Dave Jenkins, Sat.10/9/1972 at Dave’s retirement house, “
Recorded 3 hours on audio tape, transcribed from tape, but talked for 4½ hours altogether.
The text is as written in longhand by DQ, transcribed from audio tapes made of the interview with notes.
No comments or attempt to edit what was then written.
Obviously his comments are sometimes quite critical and scathing of others and the Velocette factory special engines sent out.
But then top riders all had an opinion of themselves.
Mk.7 737 bought new by D.J.
This contradicts the last interview when DJ said he got KTT738. I believe it to be KTT737.DQ.
KTT701, ex Roepke, a built up job says D.J. S/arm looks original. Never saw anything through P & R’s.
D.J rode both his KTT’s with a muffler and trade plates. “useless” he says, chokes off power unit, can’t go over 6000rpm.
D.J had a 1933 KTT ridden by Cec Weatherby in the I.O.M. D.J bought it off Bill Pickett of Rockdale who rode it on the road.
It had a megaphone 10” x 4”.
Hinton had the advantage on Nortons with their reverse cone out of corners. KTT off megaphone, but faster than Nortons when on the “bugle”.
Ahearn rode D.J’s bike – it was reverse cone megaphone equipped.
Norton’s revved to 6200, KTT’s revved higher.
KTT’s good on fast circuits.
Difficult on pit corner (
Used straight pipes at
Used Mk.7 here.
Had a derby with Bain, 10 lap race, both as fast as one another.
D.J stayed on the inside for 4 or 5 laps, Bain looking over shoulder moved to the inside line to stop him. When he didn’t look next time D.J moved to outside and went around him.
Next corner D.J got into a big slide and fell off.
1940
He nearly lapped Bain who was third.
Missed a gear on the mountain, Madsen 100 yards lead into straight.
At end of the straight, D.J moved over to inside. Cec Weatherby told him “make them think you are trying to go under, then you can’t get round them anyhow”
Madsen “sucked right in” and moved over to counter on the clutch then to get around corner and D.J swept by full bore to win by a small margin.
Photo of finish.
D.J had much more power than Madsen.
Jimmy Madsen rode a 350 Excelsior Manxman. DQ.
Eddie Waneck had a 1932 works Norton, used Dural handlebars which turned out to have a crack in them and they broke. Frame was very light, made of aircraft tubing.
After about 60 miles the KTT warmed up and he caught Madsen and was going to pass him down the straight.
At
Photo of Keith Bryen’s KTT.
Photo of Jemo, Bain on 1938 AJS at a signpost…24 hour trial.
Photo of D.J,
Photos of start of Junior and Senior 1939
Photo 1939
Mk.7 wheel different to Mk.8. 21” wheel, no fins on drum.
Airscoop bigger on Mk.7. ( not right, same brake plate .DQ)
Photo “Frith” KTT. Came out in 1948 and rode it in 1949.
Worked at P & R’s for 32 years.
Top speed of Velo down
On fuel for 100 mile races.
No actual sponsorship with oil companies, buy everything. A Vacuum oil chemist went with D.J to
Not much better top speed, better acceleration.
Monty South rode the Frith KTT. 9.9:1, 70 octane, bike pinged at Heathcote. Bathurst is 3500’ up, atmospheric pressure drops ½lb/sq.inch so increased compression ratio to compensate.
Started to rain, Monty well in lead, D.J told him keep to left and out of oil. Odd line but better in wet. He got excited and fell off…forgot, got into a slide.
Chain oiler smeared the back wheel eventually. D.J fitted a bottom rail to primary chain guard and put felt in it.
Used 10 grade oil in the gearbox. Gearbox will wear faster but worth 4 mph.
Top and bottom bevel gears there is a bush, 2-3 thou. Clearance – he made up new housings with roller bearings, machining crankcases to suit. Grind bevel shaft down a few thou.
Because ex Frith bike did not have these he feels they were not the original crankcases.
The works extra pump,…2 feed gears, one driven, the other never had a spindle at all.
Waisted the tower tube and bored a hole through it. Flexed and took shock on
D.J used larger couplings.
P & R’s had a tool maker employed.
Same as happened to
In 1938, Junior at
In the Senior, part of the head of the valve dropped off.
He had Dreadnought valves make up four valves for him. His valve radius was 7/16”, same as Repco car head engines.
Mk.7 engine
Smaller crankpin, same as crankpin in previous KTT. One piece, snap on the corner, 16 rollers all the way through.
Always 1 3/32” T.T
Last KTTs had RN, e.g Keith Bryen’s 1 3/32” RN.
First RN that D.J saw was on works bikes.
Rigid KTT’s in
In NZ….chap called Goldberg went to IOM. He used the 500, Bill White sent it over to Don Bain. It had a rattle in it. Pulled it down several times.
Tommy Jemison realised what was going on, pulled the head off it, heated it and the valve seats were loose.
Moving down with the valve and hammering back into the head with valves return.
Bain used it in 1937 Bathurst, got a rear wheel puncture and stopped every lap at the pits in later stages to pump it up….still came second.
It had an alloy head, round bevel housing, hairpins, big alloy fins.
D.J had a 1935 Mk.1 KSS road bike- much better he felt than the Mk.2 version.
Leaked oil from the rockers etc.
At a Club Day at Whynstanes, rode the Cec Weatherby KTT. It had a track Amal carb on it. He was riding it and it stopped. Broke a conrod, poked through the barrel and crankcases, found all the pieces. A chap called Sampson in Botany rode, welded it…very difficult to detect.
In 1934, no liners, Kirby engineering bored the barrel, £20 to fix, an on £5 per week.
Mk.7 cost £140 new.
Trouble with Mk.7, the rockers wore out, jumped out of gear. Wouldn’t race it in 1939. Fixed the gearbox ( machined the second gear dogs etc).
Valves, inlet 1 11/16”….exhaust 1 9/16”
Frith model.. inlet 1 13/16”….exhaust 1 9/16”
Don Bain and Tommy Jemison were fully supported.
P & R’s paid half the fuel bill, give a few free spark plugs. No pay during
£2/10/- per spark plug, last two 100 mile races plus the handicap race.
Wal Capper was responsible for reducing the length of races from 100 mile to 48 mile to make a spectacle.
D.J felt they should have been 100 milers.
Only expert and non expert.
He decided when he would go racing he needed equipment, so bought a 1933 KTT.
First race with 1933 KTT was at Schoefields near Windsor (Western outskirts of
He came second, despite falling off six times. A red gravel surface. He couldn’t remember to let off the front brake in time.
He rode it at Hartley Vale (circuit about half way to
In the Junior he got up to second behind Don Bain during the race. The rear 20” wheel ( could only buy 3” x 20 tyres in those days), when the wheel bottomed it pinched the tube and punctured, two laps from the finish.
D.J later discovered you could race on a flat tyre….
In 1940 at
He then ended the conversation.
D.J won the Junior, Madsen second, Bain third, one lap behind.
Velocette hadn’t won at
Back at work on Tuesday.
Perc Williams called him back into his office with Stuart Williams. They wanted the bike to put in the display window – no dice said D.J.
Pay my expenses.
He then made them buy it back for £150 and he would ride it.
After WW2, still trouble with P & R’s, but they cleared it up and he rode.
Jemison was only good with pushrod engines.
1941 Eric McPherson rode Jemison’s MOV, claimed it was very smooth.
MOV flywheels….Jemison’s were really light.
Hansen rode Jemison’s older MOV racer. His later one had a bronze cylinder head.
D.J felt the attempt by Ewald Kluge (on the 250
The 101mph attempt ( by Tommy Jemison, on a modified version of his MOV racer) was at Liverpool, from the Bringelly turnoff back towards
Tyres were 80psi, all but the centre blocks were cut off. Used WM1 rims front and rear, narrow tyres.
It ran on alcohol, with a 1 1/16” bore carb.
Extended the bellmouth of the carb. to 3”. Made up a 2” spacer.
He noticed a white swirl around the bellmouth around 7000rpm, acceleration improved but still a white halo. He then put a 2” block between the head and it really went. Nobody was wise to it.
He got the idea from an article in "The MotorCycle" around 1928-29 on a speed attempt by FN. It had a carb near the rear wheel – gigantic spacer. Obviously overdid it a bit.
Mk.8 KTT…
Experimented with exhaust system, found KTT system best.
1” off, power in higher up.
2” off wouldn’t pull a gear.
The crankcase of a KTT grounds first.
Rims on Mk.7 and Mk.8 steel ( actually the Mk.8 postwar are Dunlop alloy rims. DQ)
Rear 3.25 x 20”
Front 3.00 x 21”
Keith Bryen’s and the two P & R “works” machines were the only ones with alloy rims ( again, postwar KTT were alloy. DQ)
Inside nut over the rocker spindles, arrows must be pointed outwards, both the same height rockers.
Set up valve springs, 130Lb./sq.”, 0.690” he thinks.
If the arrows are in towards the centre, the valve timing was out.
KTT mudguards and stay- alloy (??.DQ)
The valance on the rear was held in by a turn over and pressing.
They were sold as one piece.
He used manual advance…36° Advance BTDC
11.0 ounce on rod…..85% balance factor.
Goes through “the sound barrier” at 3500rpm, back mudguard really vibrates. Same for rigid and swing arm models.
Really smooth.
He set the ignition at 40° and graduated the control lever at 2°, had about a 6 mile run on
Les Slaughter, Lionel Hirst, Tony McAlpine, Dave Jenkins and Jack Forrest were having a “derby” at Heathcote.
Forrest hit a wallaby, just after daylight, he bailed off and the Norton hit a tree and ended up about 2 foot long, going about 120mph.
They called Don Bain “The Burglar”…
In a petrol consumption test, Don Bain had a small tank secreted under the main petrol tank, with a copper pipe going into the air slide hole on the top of the carb. But he did such fantastic mpg that they flagged him in and he didn’t have time to turn the auxiliary tank off. Somebody spotted the leaking fuel- Don just laughed it off….
Piston ring clearance 0.060” on the top ring with the big cylinder barrel, otherwise 0.025”.
He put it on full, made a good run and on the return it wasn’t as fat. Took it home, top ring broken.
Second ring 0.045”
Barrels on ordinary KTT smaller than the head.
Main bearings were the weakest part of a KTT.
Particularly in the double knocker.
Fit is very important, would only give ½ thou instead of 1 thou on shaft – this facilitates easy removal. Bearing life greatly increases.
Keith Connelly rode D.J’s Mk.8 after Monty South went to
MS wasn’t allowed to ride as he was a P & R’s employee and Perc. Williams stopped his employees riding for fear of litigation ( after Alan Boyle was killed at
Connelly broke a rocker at Tomago airstrip – deliberately said D.K – D.J then gave him “the boot”.
Jack Ahearn rode it in 1951 and crashed, broke both wrists, concussion. He had a bad start and crashed on the mountain section of
Frames were straightened – no new one brought out.
Bent his Mk.7 at
Mk.8…
The flywheels were wrecked – landed on the engine mainshaft. New set of flywheels made up.
Mainshafts had been knurled by Veloce to fit bearings, 7 thou runout. 7 thou preload on crankcases.
M.7 did 108mph at Heathcote.
Mk.8 did 98mph. Don Bain will confirm.
Used pistons made by A.P. North ( called “Northlite”. DQ)
He preferred genuine factory ( sand cast). Carey pistons were good.
Works Velo used Mahle forged pistons, even before WW2.
Mussett’s ex works 500 had a Mahle piston…D.J saw it.
Mussett said they cost £15 in the 1930’s.
The works barrel …warm it and the sleeve, very stepped, would come out easily.
Blaxland and May machined up liners for P & R’s.
Set up with 4 to 5 thou interference.
Had to cut away the cylinder to make the valve miss- go nearly down to the top ring – 1/32” above. The works ones only had the edge taken off.
He modified the inlet port. Put a “dish” in the port near the valve. Build up of gas behind the valve. Important which side. Gives increased turbulence.
D.J did his and Les Slaughters.
He used K17/11 cams, then he made his own cams.
D.J was the foreman in P & R Williams workshop.
Les Slaughter was the foreman in P & R’s car workshop at Woollahra.
D.J’s bike went to
He doesn’t know where Slaughters bike went.
Slaughter and D.J “fell out”.
Made his cams out of SD material ( 12½% chrome), fitted it with 1 thou interference, same as the case hardened ones but when pressed on would crack through the keyway.
Allen Boyle rode Slaughters bike – was killed at
He had the cam in 1950.
At Mt. Druitt circuit with Keith Connelly, 23 teeth on g/box, ½ up on the rear, 1½ teeth different to Slaughter.
D.J 7800rpm, Slaughter 6900rpm. Slaughter used the big rockers, the “harbour bridge” rockers.
D.J results….
1940, 1st Junior TT on Mk.7 at
1946 1st Junior TT, Mk.7 and 2nd Senior, rode MSS at
1947 3rd Junior TT , Mk.7 at
1948 fell off Mk.7 at
1949 2nd or third…( does not show in results of first three in Junior or Senior. DQ)
In senior D.J “robbed” one year. Jack Forrest stopped one lap in the pits but accredited with third with 4th for D.J. ( in 1948, in the Senior, Jack Forrest was 4th and D.J was 6th…DQ)
Les Diener never came over very often.
1950 rode at
D.J never rode at
P & R’s not interested in going interstate.
Diener winning everything in
Maurie Quincey going well in
Mussett was an agent in
Eric McPherson rode D.J’s bike during WW2, fuel line came off, filled his riding boot.
Barry Ryan served his time as an apprentice at P & R’s as a fitter and turner ( did the boring and big ends).
Despite their on track rivalry, Dave Jenkins and Don Bain got on well enough to go fishing at Hawkes Nest, north of Newcastle, NSW...
3 comments:
great stuff DQ! thanks for sharing it with us.
Pete Young
Finally, I'm catching up on some great reading and DQ has done it again with this very interesting interview and notes of Dave Jenkins riding career.
Forgive my ignorance DQ, but in the article you mention the following;
Mk.8 KTT…
Experimented with exhaust system, found KTT system best.
1” off, power in higher up.
2” off wouldn’t pull a gear.
I'm lost on this, 1", 2" off what???
Check out the Newcastle beach catch! You'd be nearly as happy as riding a Velo...
Cheers, Methanol Martin
Martin,
The reference to the 1" off, 2" off was to the exhaust system length.
Cut an inch off and the was power highr up in the rev range.
Cut 2" off and it wouldn't pull a high gear...
DQ
Post a Comment