Once a year I have my own personal Christmas and pack up to do a week end of racing at my "local" track some 260 kms away.
Last year I had a complete seizure and I was hoping for some more luck this year but wasnīt sure as the bike had been getting serious detonations on the left cylinder during the practise day I had a couple of weeks ago. Only on one cylinder though as the other one was running just perfect. Anyway we set the ignition and had another cylinder, piston etc in for the race.
I packed up and left home on Friday night or the drive down, you get a bit sentimental when you hit the road on your own so I started missing the missus and the three kids at home. I had to get a yawning from a friend so I had to take a detour so I arrived at the track at 21:45 and was worried that Iīd get a terrible parking on grass far away from everything but I got the best spot in the paddock!
Hooked up with another guy (Dennis) that has raced once on a 250 a few years back who now had rented a TSR250 and hadnīt ridden for two years. We set the yawning up, unpacked and rolled our bikes in. I threw out the matress in the back of the van and fell a sleep. As I hadnīt taped something over the windows I woke up way to early and had a hard time to fall rest anymore.
First qualifying was at 08:50 so I got up and got breakfast and met with Teddy who would be the third guy in our yawning. I have painted his RS250R but he hasnīt managed to get any stickers on the bike so I had done a few to get that vely factoly look! so I had that as a surprise to him and we started with that as soon as he was unpacked.
At 08:00, you are not allowed to run any bikes before that, I followed two stroke procedure and started her up to let everyone now it was time to wake up and that they are at a race track.
Got a bit of butterflies before we got out and the first session felt awkward as always but I had done a 1.07.099 wich was a full second and a half faster than last time I was at the track. Good riddance but still a fair bit too slow ( Fredrik Watz does the lap in mid 57s on a 250
Tanked up and choose not, what a fool, to check the pistons during the intermission to the next session. Had a good time a talked to friends. Teddy did a 1.05.4 and Dennis did a 1.06.2 on his first time on the bike.
Got out for the second practise and felt better but on the straight I heard the sound of a two stroke engine not wanting to cooperate more so I clutched it and managed to roll to the paddock, I managed to lower my time slightly to 1.07.001
.while Dennis was down to 1.03.733 and Teddy 1.04.056.
Bad feeling as the spark plug was way to silver to be good and you could see aluminium coating it
get the cylinder head off and looking down the cylinder is not a pretty sight as the pistons is so detonated that you can actually see the piston ring with the piston in the cylinder
.serious heat has been going on. The weird thing is that the water was running just fine with 56-58 C but the EGT was reading way off the chart as the highest temp on the seized cylinder was at 488 C and the other one was at 590 C
For some reason that cylinder was ithe rnot getting enough fuel, sucking air trough the exhaust or the ignition was way off.
We stripped the carb and found a small piece of tank foam inside the power jet. We also checked the solenoids and they were acting the same on both cylinders. New cylinder and a used piston was thrown in. Assembled it all in time for the race and crossed my fingers.
As usual I got a fairly crap start but I managed to pass some guys on the first two laps and managed to get behind a faster guy so I felt the pace was a bit better but on lap eight I had the exact same thing happening as in the second Q and I clutched and rolled to the paddock. Clearly the foam wasnīt the problem. Setting a new personal best with 1.06.501 didnīt help much
A bit depressing but eventually I got going and ripped the bike apart and it looked exactly the same. Left cylinder fine and the right one terrible with exactly the same pattern and a seized piston.
I had a lot of help, as usual from fellow 250 maniac Anders Kihlander (he runs 58.4 times on his Aprilia RSV250 at this track) so we checked everything we could check. Ignition, solenoids again, stripped the carbs, synchronized the power valves and carbs, checked the exhaust for cracks, checked reeds and carb mount but we just couldnīt see any major problem so we opted to run the cylinder really safe and went from a 0.7mm squish to a 1.3mm wich means the compression ratio will be very low and hence reducing the risk of detonations.
For Sunday we decided that Iīd just do four or five laps and then get in so I could check if the changes had worked.After the first session I went in and stripped the head and it all looked fie and as it should do. Nice!
For the second practise we geared the bike differently with the idea to be aable to ru second instead of first as it was just too snappy. It started terrible as I didnīt have any feeling and just tried to hard so I went in to the pit lane and sat for a minute, checked the times and my best was a 1.07.9! So bad!
Got out again ad really tried to concentrate at getting the entries right and with more speed so that I could run second as planed and it really started to feel nice and it felt much faster.
I managed to set several 1.06.5 times and lower with a best of 1.06.110. Whohooo! I had lowered my personal best with 1.8 seconds since last year.
Something positive, and the cylinder looked great so I was happy with that.
Dennis was storming to pole with a 1.01.9, second day on the bike
I was going to start as 11th, the class is a real mix of 125GP bikes with mostly fast, young guys, some older gentlemen on 250GPs, some Aprilia RS250s, one Kwacker ZXR400 and two SV650s..
I am lousy at starting and did by my accounts fairly ok and passed Teddy on the brakes in to the first corner only for him to pass me getting in to the corner leading on to the main straight, this is my real bogey corner at this track as I really have no entry speed. Going down the straight I used the power to pass som e of the small guys on 125s.
Passing the line for the first time I had the first of the two SV650s right in sight and I was determined to get by him but I felt the clutch starting to slip a bit and when we got on the main straight were I usually can pass them with ease it got even worse so I had to start short shifting and loosing momentum. Damn!
From here on it was just a struggle and I put the nail in my own coffin on the eight lap when I saw that my AIM logger had switched off, I log the EGT so it is valuable, I used my left hand to turn it on again going down the straight when the bike just went dead, silent and no revs. Because of the problems I had experienced I thought that it had seized again! After the race I got in and stripped both heads and they both looked great
.strange so I put it back together and she started like a sweat dream.
When I started recalling what must have happened I got to the conclusion that I accidently turned the ignition off when grabbing the handlebar after turning the AIM logger on! What a fucking stupid thing to do!
Anyway I am fairly pleased with the fact that I managed to run a much better pace than last year. The only problem is that I still do not know exactly what caused the melt pistons. I will raise the compression again and see what happens but it is annoying that we didnīt find the problem.
Hopefully I can do one more race this year and I will be back with more rants then!