RD350 YPVS Fork modifications

I have decided to leave the 350 at home this weekend, because I need to modify the forks and change the piston rings. I started out by removing the forks, and starting the modifications to the damping rods in order to install the Gold valves. See the attached photo half way through. It was pretty difficult to remove the inside tube, as it is a push fit, and I had to use a drift through the bottom end of the damping rod. Also the holes do not exactly match up with what is in the Gold valve documents, hmmm... maybe my forks have already been through some modification.

Technical Update

Ok back from holidays now, and the bike needs some work! 

I have received new piston rings for the RD 350, and some stiffer fork springs and gold valves, this in preparation for the endurance in September at Croix-en-Ternois, so these all need to be fitted.

For the RG500, after my experiences with no filters, I have decided to leave it without the filter foam, but the big question is still which jets? I ended up with 240's in the last race at Pau and I think I was still too rich, which means I could have probably done better with 230's. The temperature at Pau was around 30 degrees C, and the weather forecast for Carole at the end of the month is currently around 20 degrees C, which means we will lose 10 degrees, which is roughly equivalent to richening by one size, so the game plan is to start with 240's at Carole - and see.

I bought a ZXR 750 radiator off evil bay during the summer, and wanted to fit it, however it is really dirty and difficult to clean (despite 3 hot cycles in the dishwasher!), so this will probably wait until I have more time. I found some nice flexible silicon water hoses (SAMCO) which will enable me to fit it, if I can find the space in the fairing! In the mean time I removed the RG radiator and spent a few sunny afternoons straightening all the fins on the rad to ensure it works as well as designed, about 25% of the fins were bent over, which must have an impact on it's cooling capacity. Again, first test is Carole on the 29th August.

I will need to bleed the brakes again this weekend, and finish off bits and bobs before racing in 2 weeks.

Two strokes forever!

Take a look at the full article here :-

Two Strokes strike back! 

But one quote from Harold Bartol (famous Dutch 2 stroke tuner and KTM Race manager) :-

That’s no wonder, says Harald Bartol, two-stroke engineering luminary and technical director of KTM’s grand prix activities: “When I look at two strokes I see only advantages – the power, the weight, the cost and complexity. And the riding dynamics of two-stroke 250s are very close to the 800cc MotoGP bikes. If I were making a sportsbike for the road I would choose a 500cc V4 two-stroke. I have absolutely no doubt it would be superior to the current superbikes, and be possible with existing legislation.”

Le Vigeant cancelled

Just a quick note before I leave on holiday. Unfortunately Le Vigeant has been cancelled, apparently a miscommunication between the organiser and our club, means we have not been planned for the weekend!

Anyway that means the next race will be at Carole at the end of August - see you there!

Technical Update

Just a quick note to remind myself what I have done to the bike recently. After Pau (too rich) I removed the difficult screw in the carb on cylinder 3, and installed 4th ball valve, I installed a 240 main jet and checked the needle setting (2 slots = standard). I also adjusted the float height to 19mm with no gasket in place as recommended by LanceGamma.

I also took of all other carbs and redid the float heights. All carbs are now at 240 mains, needle height 2, and float height 19mms.

I also checked the plugs and they were all pretty rich, which means I can probably go down to 230's for Le Vigeant.

I have received a second hand radiator from a Kawasaki ZXR 750, which although in good condition is really dirty, so I will need to clean it up, and investigate if it will actually fit (physically) inside the fairing - this should end any cooling issues I may have, the temperature is still going to around 85-90 degrees C, which is robbing me of horsepower...

We now have 5 weeks until Le Vigeant, so time for a holiday from the bike! Speak soon..... Dave

Race2 at Pau

Race 1 at Pau