My Rev3 has recently started to run very hot. Last week I noticed it starting to pink a bit and this got progressively worse. The fan's on all the time and although it hasn't actually boiled over I think it was pretty close. It also seems to have quite literally burned most of the packing out of the silencer and it's generally pretty unhappy.

I assumed that I'd managed to put a hole or tear in one of the carb boots but they both seem OK. I've pulled the flywheel and the woordruff key's fine and the timing's spot-on. The exhaust isn't badly carboned up (in fact, it's pretty clean). I've stripped the carb and everything seems OK there too.

At this point I'm wondering if there's a problem with the cooling system. There's plenty of coolant in there so that's not the problem but I can't see an easy way of testing the pump. Is there a way? Would it be worth draining and flushing the system to eliminate the possibility of blockages etc. and what's the best way to achieve this? Any other ideas?

Many thanks for any and all advice/suggestions!

The pinking could be down to something daft like a crap batch of fuel? have you tried a new plug? When was the last time you changed the coolant?

If this was a issue on my bike my first things to do would be drain the coolant check the case for the dreaded corrosion! put a new mix in 50/50, change the plug, and drain all fuel out and re fil with a decent high octane fuel with your correct oil mix.

Neon, like barry said could well be a bad batch of fuel or oil come to think of it. Go and get a new can and oil and see if that makes a difference and swap the plug at the same time. I would have thought if you had a blockage in the system the water would have p****d out everywhere by now. Could be float heights or blocked jets as well so give the carby a good clean if the fuel doesnt cure it.

Did the plug look white? or normal colour? If youve got a local Shell garage try a can of V Force well worth the little extra money

Thanks guys, I've stripped and cleaned everything, drained the tank, drained and flushed the cooling system and ordered some new plugs since I'd run out (including a couple of them new fangled Iridium jobbies, just to see if they make any difference at all or if lastplacebrad is talking bullplop as usual). I've also removed and thoroughly cleaned the radiator, just in case. I'll get a can full of V-Force tomorrow and see how it goes.

Interestingly, the "plug advisor" utility thing at http://www.sparkplugs.co.uk suggests an NGK BPR7ES for the Rev3

Interestingly, the "plug advisor" utility thing at http://www.sparkplugs.co.uk suggests an NGK BPR7ES for the Rev3

Good luck with it, the heat seven plug is a cooler plug, they have those in as stock abroad where it is hotter I think, over here it helps to have a warmer plug in, although I sometimes run a heat six in summer if it starts pinking.

Bob

Sounds alot like a possible loose, wore out waterpump impellar.

My Techno was doing that last year,when I pulled the cover and snap ring off the impellar nearly fell out (really loose) on the shaft.

The new one took a bit of force to go on.

She's been running perfect since.

Just a thought.

Neon mate, hows the bike now? is it sorted? and what do you recon the problem was in the end?

Neon mate, hows the bike now? is it sorted? and what do you recon the problem was in the end?

Sorry to say that it's still not sorted and I'm totally baffled. DNF'd a trial today because of it - the bike was still knocking badly when chopping the throttle and running very "flat" (didn't want to pick up from idle and rev out cleanly). Not what you want when a lot of the sections involve very steep blasts up banks and over root with little run-up. It certainly feels as though it's running weak. The best way I describe it is when backing off the throttle from high revs it goes "KNOCK.....ding.....ding.....ding.....ding.....ding.....splutter"

I've stripped and cleaned the carb, repacked the sliencer, flushed and replaced the coolant (checking that the impleller is working properly), replaced the plug and checked for air leaks (none found). The fuel valve in the carb (which I've had problems with in past) is working and the float height is correct. The timing is correct according to the information on beta-uk.com. I'll going to pull 'er to bits again this week and re-check everything but if anyone has any bright ideas, I'm all ears!

EDIT: I'm using a different fuel and oil too.

Edited May 20, 200719 yr by neonsurge

Bloody annoying then Neon have you tried switching the choke on when its hot? if it runs alot better it could well be fuel starvation. Only thing off hand I can think of are the reeds or the floats sticking, good luck with it, might be time to take it to a dealer to get it sorted

Up till the last trial, my bike was boiling over and knocking. It isnt even normal in hotter conditions in OZ, but this was on a cooler day.

I found the BellRay synthetic coolant I was using had crusted and solidified when boiled due to a crap batch of fuel previously. Now the radiator had blocked fins internally, water pump full of chalky stuff and hoses, flushed barrel. I am not impressed.

Have now epoxy coated water pump and now using the green glycol coolant. Tried her out this weekend gone and all good.

Edited May 21, 200719 yr by subanator

Hmmmmmnnn, Has it "ever" boiled over??

Hmmmmmnnn, Has it "ever" boiled over??

It's never actually boiled over (yet). I gave it another short run earlier and now I'm convinced that it's a fuelling issue - it would occasionally cough like it was about to run dry and if I backed off the throttle it would pick up again. Don't know what could be causing it since I've checked and re-checked the carb but I guess it's time to take another look. I might try to borrow a carb from someone and see if it makes any difference.

OK, remember when I said I'd checked the timing? Well I did but I didn't compare what was actually set on my bike with the diagrams and photos I printed off ages ago. Turns out that although the stator adjuster screws were 2.2mm from the end of the slot, they were 2.2mm from the WRONG end of the slot. Closer inspection revealed that the screws were actually loose and the stator had been gradually rotating on its own. Doh! I've reset the timing PROPERLY and she now runs great.

Yes, I'm a doufus