Yes they are easy to see. Remove the saddle and the side panels and remove the 8mm bolts that hold the tank down. The small hose going to the petcock is the vacuum line. With the tank up check to see if the enrichner slide is moving when you turn the choke to on. The slid sets in front of the carbs just below the carb piston housings. It have elongated holes so that it can move. When you are standing on the left side of the bike, on the petcock side, the enrichner slide should move away from you. With pressuer on the choke, push the slide away from you and see if it moves more.

 

Quick update:

Nothing I could assess helped it. If I could coax her to run until warm then she's fine. I managed to get her to a mechanic in this fashion, but then warm she was impossible to diagnose. However he was able to catergorically state it wasn't electrical.

It died again this morning, again after running for a minute, just beginning to warm then nada... Dead and refusing to start at all.

I was away from my place so I've used a different mechanic, this guy specialises in older bikes and customs... feeling a bit more confident in his diagnostics. He's changed the battery, changed the spark plugs, checked that the fuel lines and tank breathers are working as they should. He's keeping it overnight to see if it fails to start after another full cold night.

If it does the same act, 1 minute run then stall dead, then he seems sure it'll be the valve clearances, and will take the top case off the engine and get to it.

Hopefully this will nail it...

 

Further quick update. The new battery and plugs cracked it!

For two days, then the old problem has come back. Running for one minute, then not. Now it won't start at all...

Back to the same guy and on with the valve clearance adjustments next.

I swear, the sound of a CBR1000F not starting is about the saddest I know.

 

Hang in there man! Hopefully you will be riding soon and it will run a lot better too!

 

That makes no sense to me, but it must mean something to some of the wizened set around here. My blood pressure goes up just thinking about this.

 

Surely, if the new battery and plugs worked for two days, it must be a charging problem. I just don't understand how valve clearances could be the problem mate. If it was (and they'd have to be wildly out) the new battery and plugs wouldn't have worked at all. In my opinion a compression test would show if the valves are closing properly and even if the clearances were so great that the valves weren't opening enough, it'd still run and you'd hear a hell of a lot of rattling which wouldn't go away when warm.

I'm no mechanic (by a long way!) but I just can't see the logic in the valve clearance theory.

Hang in there mate..when she roars into life again it'll all be forgotten.

BTW, what do the new plugs look like?

 

Agree with you Dave

Check R/R and then the alternator & alternator damper ...............

 

I'm willing to bet
If you check your battery, you'll find it's a little bit flat

I would say your regulator/rectifier isn't charging the battery.
Check the voltage at the battery.

If you can jump start it, then it's either the reg/rec or the stator, or if you're really lucky, a bad earth.

My 2c worth.

 

Man, I certainly appreciate the support for a new guy!

I don't think it can be the electrics, and now neither the mechanic or I think it's the valve clearances...

Here's why: they collected the bike in a van, and before unloading it - when they got back to the workshop, they tried to turn it over, and she fired right up...

Has to be a fuel blockage or vacuum issue? I've taken the liberty of copying some of the ideas here to run past them - thanks again for all the above.

Needless to say, will report back as I hear more..!

Mark

 

Make sure they check that petcock. Not the tap, the vacuum valve, they're a pain in the **** when they play up. Don't just suck on the vacuum pipe and relax if fuel flows, pull the ba5tard apart, clean it right out and check the rubber. Good luck! I hope it's something simple and cheap.

Don't loose faith mate, it's a Honda!