Allens Performance Ltd.

Endurance Legends 4 hour endurance race review, Snetterton circuit, 17th and 18th of October 2015

October 24th, 2015

Thanks be to Darin Frow and Rob Beale of Classic Bike Trackdays/Endurance Legends for taking up the massive labour of love and financial commitment required

to make this event happen. The Classic Racing Motorcycle Club also got behind the idea and made it possible. I’ve heard talk for years about the desire and concept to bring classic motorcycle endurance racing to the UK, but it still caught me by surprise when it actually happened!

Allens Performance Classic Endurance Honda VFR750 RC24 Team

The Allens Performance classic Endurance Legends race team conisiting of Alan Hudson, Chris Withey, Steve Panter, Simon Hindley, Nolan Freebury and the Honda RC24 VFR750


In order to give ourselves the best chance, I decided to find a nice, reliable (haha) Honda VFR750 and enter the F2 class. Although the bike was purchased early in the year, the various parts and work all came together very late in the day. I tried the bike on the road months ago, but the practice on Saturday morning at Snetterton was the first time our VFR had ever actually taken to the track.


Previously a 70,000, 3 owner non running bike bought for £400, it seemed very fit and willing. Dyno testing and a little rejetting of the carburettors further confirmed that it was producing 90hp at the rear wheel. Obviously 70,000 miles is enough to get these old Hondas nicely loosened up!


Race preparation involved the usual service, removal of road specific pats, lockwiring of certain fasteners, swapping coolant for water, adding a race exhaust, rearsets race bodywork, Avon AM22/23 tyres, new pads, a new Nitron shock at the back, Hyperpro springs and S1 Suspension cartridge emulators in the forks.


Conditions were fairly good for qualifying. We got 12th of 16. The carburettor setup was spot on. There were no glitches or flat spots, just seamless drive! Straight line speed wasn’t an issue but we all needed to gel with the untested bike. We reasoned that in a four hour race the starting position was not crucial in any case. Gear selection issues were our biggest problem but we managed to mitigate the issue before race day arrived.


Simon Hindley dismounting after his session


In the garage Alan Hudson had us all well organised, sorting out who was responsible for each task, keeping track of laps, lap times and even cooking a fried breakfast! Nolan Freebury kept the bike topped up with fuel, wearing full leathers for fire protection and wielding the quick fill tank. (After Alan repaired it!) Nolan has since decided that he must get his Clubman’s licence in order to compete next year!


The weather could have been a lot better! Words that spring to mind are damp, greasy wet, wetter and cold. A garnish of oil here and there too! Since this event was run under the umbrella of the Classic Racing Motorcycle Club, wet tyres were not permitted! So, with caution I executed the start (running across the track to the bike was a novelty) and all seemed to go well. The track was wet but drying slowly. I was able to pass quite a few bikes on the first lap while feeling fairly safe about it. A few laps later, he track began to dry and I was able to push harder. However, arriving at the bomb hole amidst the wreckage of Phase One’s formula one bike did give me pause for thought!


Getting the bike safely onto its stand

Just as it seemed that the track would get dry, the rain returned with a vengeance! I had eventually remembered to check for the pitboard and missed it the first time it was shown. It’s safe to say that visibility was not good! I did my first ever pit stop. I was careful to halt at the stop line and observe the pit lane speed limit. It was actually a relief to step off the bike and relax while the next rider, Chris Withey mounted up. I was flabbergasted when the guys told me that our team was running second in class! I was almost on cloud nine! I tried not to get too excited, a I knew there was plenty of time for things to go wrong.


HRC Screwdriver releases the tank cap

Unfortunately, soon after I began to clean my helmet it became apparent that Chris was having problems. He’d broken down at Corrams and manfully pushed our big old VFR back to the pitlane in the rain. Our first suspicion was that the wet weather had caused us some ignition problems. We sprayed everything with a good deal of silicone, wrapped a few things in tape and the bike ran. Off he went again and stopped halfway up the pitlane. Another fiddle and the bike flew off while the rest of us bit our nails furrowed our brows. Chris and the VFR didn’t reappear for quite a while. Eventually they returned in the recovery van!

Precious minutes were wasted while we tore bodywork off, checked and rechecked electrical parts, consulted wiring diagrams, pulled hair out, all to no avail! Eventually it was discovered that pulling the wiring loom around at the front of the bike caused the problem to disappear. We got it cable tied in an operational position and sent the bike out again.


I was told that the drama cost us over twenty laps! Although the bike gave no further problems, the damage was done. Despite all three of us riding at a good pace considering conditions, it was impossible to catch the others teams except in cases where they had their own problems. The most dramatic event was a miscalculation of fuel load leading to an unfortunate splutter around Corrams before Chris made his stop. We worked out what had happened and refilled the bike! Brows were mopped after that pitstop.


Drama and unwelcome ignition problems!

Simon Hindley was our rider at the helm during the final leg of the race. Although the whole race had been run in challenging weather and we’d all had our share of scary moments, conditions were getting worse and worse with each lap. He did well to keep the bike off the ground and it seemed the closer he got to the flag, the more slippery and difficult the circuit got! The whole team was overjoyed when Simon crossed that finishing line on the final lap!

We’re successfully addicted. Next year we hope we can get a real result!

Writing: by Steve Panter

Pictures by Claire Mackintosh, Clickers Photography Ltd. All rights reserved.


Joy after Simon finishes the race!



Cheerful team in Parke Ferme


Allens Performance: Delivering Carburation Innovation Since 1983

October 9th, 2015

You will find most knowledgeable, long standing people in the motorcycle industry will already know about Allens Performance and its reputation.
Anyone who has looked for long at a carburettor has probably marvelled at the complex appearance of these precision instruments intended to give you the perfect mixture of well atomised fuel in air despite the demands of varied load and speed conditions.

Making all this happen is not a black art as some would have you believe. In essence, a carburettor is a simple collection of pipes, metering holes, fed by a pressure difference and a pool of fuel. However because there are so many unknown quantities involved it does require plenty understanding, logic, experimentation and experience to get things right. Allens Performance will help you achieve the perfect burn!

Allens Performance can help with mail order. Genuine parts for Mikuni and Keihin (aftermarket) carburettors, and can now also offer a limited range of parts for Mikuni OEM carbs. Additional parts Tomaselli, Domino and Leonelli controls, custom made throttle cables, Aktive reeds (for road race and MX, etc) Other services Allens Performance can provide:

  • Carburettor servicing, reconditioning and restoration
  • Ultrasonic cleaning and media blasting
  • Engineering solutions to repair and rescue difficult to obtain carburettors and parts
  • Consultation and setup service on location available

Suzuki XF650 Freewind Special Carb Set with TPS

December 15th, 2014

Another job to keep the Allens workshop busy! Not the billet Throttle position sensor adaptor on this special rack of smoothbore Keihin CR33 carbs for a Suzuki XF650 Freewind engine powered CCM. Pictured here next to the original Mikuni BSR CV carbs

.Special Rack of CR33 Smoothbores for Suzuki XF650 Freewind CCM with TPS

What are Jets/valves/metering screws?

December 10th, 2014

Jet: A component controlling flow of a fluid, restricting by means of a calibrated orifice size. In the case of a carburettor this fluid could be fuel or air.

Float Valve: A component designed to allow or prevent the flow of fuel. A float valve prevents fuel flow when the level in your float chamber is correct. Exactly like your toilet cistern.

Metering Screw: A tapered screw allowing adjustable flow restriction of fluid. (In this case fuel and/or air.)

Float Valve

November 26th, 2014

The function of this part is to maintain a consitant fuel level in your carburettor float chamber. As the fuel drops the floats will sink, opening the valve and allowing more fuel to pass through.

Jet Size Chart

November 21st, 2014

Jet Size CC/Min Jet bore
10 0.273
15 0.335
20 0.387
25 0.432
30 0.474
35 0.511
40 0.547
45 0.580
50 0.611
55 0.641
60 0.670
65 0.697
70 0.723
75 0.749
80 0.773
85 0.797
90 0.820
95 0.843
100 0.865
105 0.886
110 0.907
115 0.927
120 0.947
130 0.986
140 1.023
150 1.059
160 1.094
170 1.127
180 1.160
190 1.192
200 1.223
210 1.253
220 1.282
230 1.311
240 1.339
250 1.367
260 1.394
270 1.421
280 1.447
290 1.472
300 1.498
310 1.522
320 1.547
330 1.571
340 1.594
350 1.617
360 1.640
370 1.663
380 1.685
390 1.707
400 1.729
410 1.751
420 1.772
430 1.793
440 1.814
450 1.834
460 1.854
470 1.874
480 1.894
490 1.914
500 1.933
510 1.953
520 1.972
530 1.990
540 2.009
550 2.028
560 2.046
570 2.064
580 2.082
590 2.100
600 2.118
610 2.135
620 2.153
630 2.170
640 2.187
650 2.204
660 2.221
670 2.238
680 2.255
690 2.271
700 2.287
710 2.304
720 2.320
730 2.336
740 2.352
750 2.368
760 2.384
770 2.399
780 2.415
790 2.430
800 2.445
820 2.476
840 2.506
860 2.535
880 2.565
900 2.594
950 2.665
1000 2.734
1050 2.802
1100 2.868
1150 2.932
1200 2.995
1250 3.057
1300 3.117
1350 3.177
1400 3.235
1500 3.349
1600 3.458
1700 3.565
1800 3.668
1900 3.769
2000 3.867
2100 3.962
2200 4.055
2300 4.146
2400 4.236
2500 4.323

The wizards at Allens Performance

January 15th, 2011

Classic Motorcycle Mechanics January 2011

Here at Allens Performance we are pleased as punch to be featured in this month’s Classic Motorcycle Mechanics magazine. Here’s how the article starts…

“Intricate detailed and demanding: there’s a real black art about the carburettor, but not to the wizards at Allens Performance.”

Words: Bertie Simmonds Pictures: Joe Dick

Classic Motorcycle Mechanics – January 2011 (Download the 6 page article here in PDF format)

Visit for more from this excellent publication.

125 Bantam Class

March 26th, 2000

125 Bantam has become a championship contender after only 3 years development!