bluedog59

My friend had exactly the same problem ( on a single cylinder engine ) and went through 3 carbs before he stuck my "leak down tester" on it. Exhaust valve leaking due to poor condition valve seat and carbon build up. Pointless trying to set carbs if the engine is not in good fettle. Who said anything about a blocked oil filter ?

Give the engine a service, oil/filter/tappets etc. Pointless trying to set carbs otherwise.

A smaller volume above the diaphragms would also make the slides rise quicker. Whether this made any noticeable difference or affected the jetting is another matter.

"Some teams were blatantly cheating" ?! I think "They were all cheating but some didn't cheat enough to win" would be nearer the truth.

Spoke wheel building, best done in peace and quiet with the phone turned off.............and a beer waiting in the fridge for when it finally spins straight and true.

How's the prep going for this weekend ? The local weather forecast for Donington shows rain on Friday late morning/lunchtime then reasonably sunny with no rain for Sat and Sun. Good luck and have fun.

But not quite fabtastic.

And she can tell what you've been up to now you've posted photographic evidence.

Does it run smooth and quiet when you put the cap back on and the revs go up ?

Head/downpipes joint would be my first place to check. I don't think it's anything major mechanical or it would sound like a sack of spanners when you rev it.

Blowing exhaust ?

Getting "temporarily uncertain of your precise location" is all part of the fun. On one detour back from Magny-Cours we pulled over into a layby to ask two French bike cop where we were. After much laughing, they turned two pages in the map book "ici Monsieur". A quick confer between them and we were told to follow and they would put us back on course. What followed was a high speed 60 odd mile blast with two Brit registered bikes chasing two loony cops, blue lights and sirens all the way.

SAT NAV ?! I remember going to the French GP at Magny-Cours in '92 with nothing but a few notes on the side of a packet of Woodbine and the sun to guide us. Only got lost 12 times and had to turn back at the Spanish border twice, them were the days. Bloody youth of today don't know they're born.

Well done, another good weekend. When you're doing a track walk it's good to remember that being where you need to be coming out of the corner is dictated by your entry into it. When you've walked through a corner stop and look back up the track to see if the line you're thinking of will put you in the right place. On a series of bends that all link together, walk back up the track and check that your entry into the first is correct. Hall bends at Cadwell is a good example, you can come whistling through the first bit but you'll be in totally the wrong place for the hairpin which kills your exit speed which then affects you all the way down the straight. At Donington Park the apex of Hollywood is further down the hill than you think and thus allows a straighter line through the left midway down the hill. Take a look back up the track from the Old Hairpin and you can see the line you need. Sorry if that's a bit long winded and sounds obvious but give it a try on your next track walk and see if it helps.

The FCR39mx on my DR650 measures, Spigot o/d 50mm. Top of spigot to top of carb 66mm (measured to carb top over slide). Total height, drain plug to slide cap, 178mm. Not sure if MX version differs from road version but I hope this helps.