So as you are already aware we prepare our own race bikes, anyone that goes racing knows this takes an awful lot of time, energy and patience. Lee is a time served mechanical engineer and therefore enjoys maintaining his own bikes, machining new parts, rebuilding engines and dabbling with light tuning work where he can. Mike is a mechanic by trade so is also a hands on type, however that said we know our limits and do rely on help from the experts when it comes to high performance race tuning though.
The next three page's outline's the specification of each of our machines, details such as the class's they are eligible for and anything else interesting we can think of. We have also covered in detail the development and maintenance work that we do to the bikes, this should give a good insight into the machines and the work we have put into them over the seasons we've been racing.
The next three page's outline's the specification of each of our machines, details such as the class's they are eligible for and anything else interesting we can think of. We have also covered in detail the development and maintenance work that we do to the bikes, this should give a good insight into the machines and the work we have put into them over the seasons we've been racing.
Harris Yamaha 350LC YPVS
Machine Overview:
This is Lee's Harris 'Lowboy' framed Yamaha 350 YPVS race bike. It's a fantastic looking bit of kit and has the performance to match - as it's a proven race winning bike in recent years. This bike will be used to compete in the post classic 750cc clubman class with CRMC, and also various other trophy race's the CRMC put on throughout the season.
I bought this bike from a top bloke by the name of Herbie Moses, who had put a lot of time and money into building the bike as a sponsor, originally for Alex Sinclair with help from Alex's dad Ian Sinclair. It has since been in the hands of Richard Wilson who also won races on it, needless to say I'm very pleased to be the latest owner of this bike, and will be trying my best to do it justice out on the circuit. Think it goes without saying that this bike is a world apart from anything I've raced before, particularly the handling characteristics that will take some serious learning and getting used to.
The Harris frame has been modified to take a 350LC YPVS motor so that the bike can be used as an F2 machine. I presume that It once would have carried a TZ motor, and the feedback from Harris is that some of the frame tubing is of heavier gauge pointing toward the idea that it may have been built to race over on the Island and certainly on the roads.
Who knows - maybe one day I'll put a TZ motor back into the bike and have a GP spec machine to play with.
I bought this bike from a top bloke by the name of Herbie Moses, who had put a lot of time and money into building the bike as a sponsor, originally for Alex Sinclair with help from Alex's dad Ian Sinclair. It has since been in the hands of Richard Wilson who also won races on it, needless to say I'm very pleased to be the latest owner of this bike, and will be trying my best to do it justice out on the circuit. Think it goes without saying that this bike is a world apart from anything I've raced before, particularly the handling characteristics that will take some serious learning and getting used to.
The Harris frame has been modified to take a 350LC YPVS motor so that the bike can be used as an F2 machine. I presume that It once would have carried a TZ motor, and the feedback from Harris is that some of the frame tubing is of heavier gauge pointing toward the idea that it may have been built to race over on the Island and certainly on the roads.
Who knows - maybe one day I'll put a TZ motor back into the bike and have a GP spec machine to play with.
Machine Specification:
Engine - 1983 Yamaha 350LC YPVS, Dick Sullivan race tuned cylinders and head, Dick Sullivan modified gearbox, Wossner pistons, heavy duty gearbox bearings, billet power valves, banshee crank, straight cut primary gears, billet clutch basket, V-Force reeds and reed blocks, 34mm TZ race Mikuni carburettors, Oversize TZ Hi-capacity radiator, Samco water hoses.
Ignition - Mestre race system with servo power valve control.
Frame - Harris Low-line or 'LowBoy' frame. Harris Swing-arm.
Rear Brake - Brembo remote cylinder and caliper. 1 off foot peg / lever and mounting.
Front Brakes - Twin front disk with AP Lockheed calipers and Nissin master cylinder.
Front Suspension - 36mm TZ forks and yokes, progressive fork springs.
Rear Suspension - Yamaha TZ350F/G unit with upgraded & re-valved internals.
Bodywork - TZ350 race fairing, option of TZ350G or Harris seat units. Harris tank.
Wheels - Astralites in matt black, front 18x2.5" fitted with an Avon AM22 medium. Rear 18 x 3.5'' fitted with an Avon 130/70 medium.
Pipes - Bespoke Tony Green fabricated expansion chambers to match Dick Sullivan's cylinder porting.
Other - Talon sprockets (no cush drive), steering damper, Domino twin pull throttle, Domino clutch lever, Goodridge brake hoses, Scitsu Tacho, Motul 800 2-stroke Oil.
Engine Output - 74 hp peak @ 11000rpm. Max revs 11500rpm.
Ignition - Mestre race system with servo power valve control.
Frame - Harris Low-line or 'LowBoy' frame. Harris Swing-arm.
Rear Brake - Brembo remote cylinder and caliper. 1 off foot peg / lever and mounting.
Front Brakes - Twin front disk with AP Lockheed calipers and Nissin master cylinder.
Front Suspension - 36mm TZ forks and yokes, progressive fork springs.
Rear Suspension - Yamaha TZ350F/G unit with upgraded & re-valved internals.
Bodywork - TZ350 race fairing, option of TZ350G or Harris seat units. Harris tank.
Wheels - Astralites in matt black, front 18x2.5" fitted with an Avon AM22 medium. Rear 18 x 3.5'' fitted with an Avon 130/70 medium.
Pipes - Bespoke Tony Green fabricated expansion chambers to match Dick Sullivan's cylinder porting.
Other - Talon sprockets (no cush drive), steering damper, Domino twin pull throttle, Domino clutch lever, Goodridge brake hoses, Scitsu Tacho, Motul 800 2-stroke Oil.
Engine Output - 74 hp peak @ 11000rpm. Max revs 11500rpm.
Development
23/09/2013 - 2014 PRE SEASON WORK BEGINS:

To be honest - this is already a well prepared and proven race winning machine, so we are only planning to make some minor changes over the winter ready for next season. The previous owner of the bike, Herbie Moses, recommended some small tweak's he had planned to make had he kept the bike, to take it up a notch reliability wise. Also some improvements with the handling side of things could be made having spoken to the last person who used the bike for racing.
When I bought the bike it came with 2 engines, one is currently stripped (crank had gone) and the other is what we can see here fitted in the photograph. The engine shown in the photograph is in decent working order and is fitted with Dick Sullivan race tuned cylinders, Wossner pistons, billet power valves, hi flow water impeller, uprated power valve bearings and heavy duty gearbox bearings. This will be my 'engine 1'.
However - In amongst the spares that came in the deal there is a brand new Banshee crank, which has had the pins welded for extra strength under load, and a nice billet clutch basket. During the closed season I'm going to take the opportunity to strip the engine that's in the bike currently, fit the banshee crank, and to take the strain off the new crank I intend to fit straight cut primary gears with the new billet clutch basket. This will give me a good strong and ultimately more reliable motor which will obviously be the main engine for next season.
This leaves me with a good spare 'engine 2', which will be built with the crank that is currently fitted in engine 1, and will have cylinders that have had some mild tuning mods. This engine will be taken to all the meetings to be used as a spare in event of engine 1 failure., fingers crossed it wont be needed!
The only other significant change I am pondering is to fit an 18" rear wheel instead of the currently fitted 17". The 18" rear Avon race tyre is a much better tyre than the 17", the 17" rear is known to struggle to heat up sufficiently. This was an issue experienced by the last rider of the machine. So I am currently on the lookout for a suitable replacement 18" Astralite wheel, hopefully I'll find a decent second hand wheel rather than having to pay big money for a brand new one. If your reading this and know somebody who has one they might sell or swap please drop me an email.....!
We've spent some time picking up spares and consumables such as levers / oil / plugs etc which will inevitably be needed next year and have also managed to pick up a 3rd engine as well, very kindly offered by a friend who has no use for it. I'll just store that one in the garage just in case.
Got a few photo's so far - but more will follow once I start rebuilding the engines to swap all the parts around....
When I bought the bike it came with 2 engines, one is currently stripped (crank had gone) and the other is what we can see here fitted in the photograph. The engine shown in the photograph is in decent working order and is fitted with Dick Sullivan race tuned cylinders, Wossner pistons, billet power valves, hi flow water impeller, uprated power valve bearings and heavy duty gearbox bearings. This will be my 'engine 1'.
However - In amongst the spares that came in the deal there is a brand new Banshee crank, which has had the pins welded for extra strength under load, and a nice billet clutch basket. During the closed season I'm going to take the opportunity to strip the engine that's in the bike currently, fit the banshee crank, and to take the strain off the new crank I intend to fit straight cut primary gears with the new billet clutch basket. This will give me a good strong and ultimately more reliable motor which will obviously be the main engine for next season.
This leaves me with a good spare 'engine 2', which will be built with the crank that is currently fitted in engine 1, and will have cylinders that have had some mild tuning mods. This engine will be taken to all the meetings to be used as a spare in event of engine 1 failure., fingers crossed it wont be needed!
The only other significant change I am pondering is to fit an 18" rear wheel instead of the currently fitted 17". The 18" rear Avon race tyre is a much better tyre than the 17", the 17" rear is known to struggle to heat up sufficiently. This was an issue experienced by the last rider of the machine. So I am currently on the lookout for a suitable replacement 18" Astralite wheel, hopefully I'll find a decent second hand wheel rather than having to pay big money for a brand new one. If your reading this and know somebody who has one they might sell or swap please drop me an email.....!
We've spent some time picking up spares and consumables such as levers / oil / plugs etc which will inevitably be needed next year and have also managed to pick up a 3rd engine as well, very kindly offered by a friend who has no use for it. I'll just store that one in the garage just in case.
Got a few photo's so far - but more will follow once I start rebuilding the engines to swap all the parts around....
14/12/2013 - SHOCK ABSORBER REPAIRED:

So having discovered that the rear shock absorber top adjuster nut and thread body was totally knackered at our brands hatch test day - the shock has since been removed to be repaired. I opted to take it to Falcon Shock Absorbers as I have dealt with them before and found their quality of service and products to be excellent. While it was there the damper action has been checked (all good) and the spring rates of the 2 springs with the shock have been checked so I know where I am.
The shock is now back on the bike, and once I have got the crank swapped over, my new straight cut primary gears fitted and engine back In ill be able to play with the suspension and get it set-up properly for me. The photo below shows the new 18'' rear Astralite that I have painted black (was very rough/tatty gold) and fitted, along with a new Avon cantilever 130 section tyre.
I have also decided on the correct seat unit for the bike as I wasn't 100% happy with either of the two that came with the bike, so I now have a later TZ seat ready for painting, very kindly supplied @ zero cost by Spike Livingstone of ragged edge racing - Thanks Spike.
While on the subject of freebies - I have also been donated another YPVS engine by a mate of mine - pretty rough to look at but in good condition and bores still standard so that will be tucked under the bench for any future development work. Racing is a very expensive habit, so its great when people chip in and offer help and bits and pieces - very much appreciated!
The shock is now back on the bike, and once I have got the crank swapped over, my new straight cut primary gears fitted and engine back In ill be able to play with the suspension and get it set-up properly for me. The photo below shows the new 18'' rear Astralite that I have painted black (was very rough/tatty gold) and fitted, along with a new Avon cantilever 130 section tyre.
I have also decided on the correct seat unit for the bike as I wasn't 100% happy with either of the two that came with the bike, so I now have a later TZ seat ready for painting, very kindly supplied @ zero cost by Spike Livingstone of ragged edge racing - Thanks Spike.
While on the subject of freebies - I have also been donated another YPVS engine by a mate of mine - pretty rough to look at but in good condition and bores still standard so that will be tucked under the bench for any future development work. Racing is a very expensive habit, so its great when people chip in and offer help and bits and pieces - very much appreciated!
06/01/2014 - SPLITTING THE MOTOR:

So as you know the plan was to split the engine, swap the existing crank for the new banshee crank, then fit the new straight cut gears & billet basket and bolting it all back together again. When I stripped the engine I did come across a few minor issue's.....
There was some damage to the L/H piston as shown in the photograph where I assume the front edge has been catching the power valve. As far as I know this can be avoided by setting the power valve up to give more clearance from the piston, so will look at this when doing the rebuild. Also once I had removed the clutch cover there appeared to be a metallic debris in the oil, worrying to say the least. However, once the clutch basket was removed all became clear - the bearing retainer bracket that bridge's both halves of the crankcase's has at some point broken, and the small missing piece from the bracket has obviously been destroyed inside the engine causing the metal in the oil. There is no damage to any of the gears in the gearbox, in fact they are in excellent condition as are the selector forks ad the drum. All the bearings are uprated heavy load bearing's, so once this engine is back together it will be as strong as its ever likely to get!
There was some damage to the L/H piston as shown in the photograph where I assume the front edge has been catching the power valve. As far as I know this can be avoided by setting the power valve up to give more clearance from the piston, so will look at this when doing the rebuild. Also once I had removed the clutch cover there appeared to be a metallic debris in the oil, worrying to say the least. However, once the clutch basket was removed all became clear - the bearing retainer bracket that bridge's both halves of the crankcase's has at some point broken, and the small missing piece from the bracket has obviously been destroyed inside the engine causing the metal in the oil. There is no damage to any of the gears in the gearbox, in fact they are in excellent condition as are the selector forks ad the drum. All the bearings are uprated heavy load bearing's, so once this engine is back together it will be as strong as its ever likely to get!
15/01/2015 - 2015 PRE SEASON BEGINS:
2014 was a very challenging year for me on the Harris F2. I had a couple of decent results on it including a couple of third's, but other than that it came down to mechanical issue's and crashes. I parted company with the bike 3 times in 2014 and a couple of them were not nice. So whats the problem?? The handling! Ive never ridden a bike that inspired less confidence in me & I struggled to get used to it from the moment I had the first crash at Pembrey. Pre-season testing and practice at Pembrey went so well I had bags of confidence, but as soon as I slid off after the hairpin at Pembrey without understanding why it happened my confidence was shattered. Follow that up with couple of more crashes and breakdowns and the season never really got going. So what are we going to change to get it sorted? A few things actually;
As with all suspension alterations, small tweaks could have a significant effect on the handling of the machine - hopefully these will help me move in the right direction with a fresh start to a new season. Some photo's of the winter work so far;
- Replace 17x3'' front Astralite with an 18x2.5'' fitment with Avon AM22 tyre
- Replace 18x2.5'' rear Astralite with an 18x3.5'' fitment with Avon AM23 tyre.
- Lengthen the shock absorber by 20mm (as recommended by a suspension expert).
- Lower the clip ons down the forks and drop the front ride height by a small amount.
As with all suspension alterations, small tweaks could have a significant effect on the handling of the machine - hopefully these will help me move in the right direction with a fresh start to a new season. Some photo's of the winter work so far;
To lengthen the shock I'm having a small boss machined to give me an extra 20mm of length at the end where the shock is bolted to the frame, pretty basic really. Terry Davies is making the extension for me, I've asked him to make 2 of differing lengths so that I can change them over and see what the effects are on the handling of the bike. I've got some data on Maxton & Nitron suggested shock lengths for a Harris TZ and the one I have fitted does come up slightly short, so hopefully I should notice a difference when I ride the bike! I'll have some photo's to post of this mod within a couple of weeks.
Meanwhile I'll be fitting the new rear tyre, putting the new wheel/tyre on the bike and taking it down to Dad's so that we can get the fairing repaired and painted up for next year. Moto71 are sending through some decals and Oils for me, so I can badge the bike up with its new sponsor and give the motor a once over / new gearbox oil.
Meanwhile I'll be fitting the new rear tyre, putting the new wheel/tyre on the bike and taking it down to Dad's so that we can get the fairing repaired and painted up for next year. Moto71 are sending through some decals and Oils for me, so I can badge the bike up with its new sponsor and give the motor a once over / new gearbox oil.
01/04/2015 - READY FOR PEMBREY:
Were all ready to go racing in 2015. The bike is looking the best it has since I've owned it and we are really looking forward to getting going with her. Having now stripped the top end and rebuilt with new power valve bushes and seals and new o rings in the head its raring to go and sounds like its got its bike back when we ran it up the road. The shock has also been successfully lengthened 5mm as planned so we can see how that affects the bike on the track.
I've spent quite some time tidying up the bike cosmetically, including repairs to the bodywork and new paint job done by Dad (which looks spot on far to good for a race bike!) and then lots of fiddly bits have been done like machining new spacers, toe pegs and various brackets, replacing nuts/bolts and washers. I also found that the bolt that secures the top of the shock to the frame had the threads rounded off so that has been changed for a pin with a bolt and washer securing each end. Probably the only bit left to do is replace the seat unit with a TZ350S seat, and then paint it to finish off the Marlboro color scheme. The tank also needs a coat of white as its a bit bruised in places. We will have to do that after Pembrey now though as these photo's were taken the day before leaving for Pembrey.
As you can see we are carrying my sponsor Moto71 decals on the fairing and also on my race helmet - they have been a real help in the lead up to the start of the season which has been great, supplying me with the quality Motul lubricants I use for the bike. Please visit their website for all your motorcycle lubricants and consumables - just click on one of the above photo's to go straight there.
As you can see we are carrying my sponsor Moto71 decals on the fairing and also on my race helmet - they have been a real help in the lead up to the start of the season which has been great, supplying me with the quality Motul lubricants I use for the bike. Please visit their website for all your motorcycle lubricants and consumables - just click on one of the above photo's to go straight there.
20/06/2015 - MID SEASON UPDATE:
After a decent start to the year things went a little wayward at Anglesey - but we found the problem! A broken reed petal can really ruin your day especially when you don't carry and spares (we will do from now on!). See photo's below;
New petals are ordered up now, so she will be back to her best in time for Donnignton Park. As you can see from the photograph on the left, one of the petals is frayed on the end - this will have been affecting the performance of the bike, and clearly the cracked petal was the end of the weekend for me. Really glad to have found a problem having been considering sending the ignition off for a test and all sorts of other complex issue's. So now I'm off on holiday for the next 3 weeks meaning I will miss brands hatch unfortunately - but were back in time for Aberdare Park and then almost straight into Donnington Park where I'll be back riding the Moto71.co.uk Harris Yamaha again. While I'm away Dad will be painting the Tank again and also hopefully re-working some of the seat paint and decals - she's almost looking how we want now just needs finishing touches.
Any questions or comments?
If you have questions about any of our bikes - be it specification / eligibility / spares / tuning, please feel free to drop me an email I will try to get back to you ASAP with answers.