Most motorcycle problems are caused by the nut that connects the handlebars to the saddle.

Valve Clearances

Share
avatar
James Higgins
Newbie
Newbie

Posts : 7

Valve Clearances

Post by James Higgins on Sun 28 Oct 2012, 7:28 pm

Decided today to have a go at checking my valve clearances as expected all where very tight exhausts between 0.18-0.20 (should be 0.25-0.27)and inlets from 0.10-0.13 (should be 0.16-0.18). And due to my cack handedness I destroyed the timing inspection cover so tried going in with an extractor and went through the entire case so having to order a new one from dave silvers.

Anyway long story short now I know all the shims need changing I think its time to hand it on to a professional. I don't think I have the time or patience to remove the cam chain tensioner etc!

But for future reference does anyone have any tips or suggestions for removing those covers? I tried oil and shocking them with a hammer before i turned them but still made mincemeat out of the ali.

Thanks in advance
Jamie
avatar
eternally_troubled
Admin
Admin

Awesome!
Posts : 3606
Location : 'ere be fens. (near Cambridge)

Re: Valve Clearances

Post by eternally_troubled on Mon 29 Oct 2012, 12:34 pm

Firstly, I suspect that you *could* do the shim replacement yourself (I did! and my bike still works :)

Secondly, I'm not surprised that those covers were stuck in, they were pretty hard to shift on mine too.

I suspect that heat and an impact driver/mallet combination might have been a good idea, however, sometimes these things are stuck solid and can't be removed without destruction, so it might not even be your fault.
avatar
louis_sutton
Laser Shark
Laser Shark

Posts : 191
Location : north london

Re: Valve Clearances

Post by louis_sutton on Sun 18 Jun 2017, 5:57 pm

sorry to resurrect an old thread, but I've just been checking the inspection caps on mine to see if they'll come off ok when I start my valve clearance.  The larger one is putting up a fight, and is in danger of rounding out.  I need to spend some time warming the case up, and then putting an allen bit on my manual impact driver to see if that will change things.

But I thought I'd ask if anyone had any tips before I got stuck in?

Cheers
Louis
avatar
sullivj
the 900
the 900

Posts : 2080
Location : Gatwick

Re: Valve Clearances

Post by sullivj on Sun 18 Jun 2017, 7:47 pm

Even on my very clean CB5, the larger one wouldn't turn at all, and very quickly rounded out.  I ended up hammering a slot into the edge, which I could get a screwdriver into to turn it out.

Obviously, I then needed a new one.

avatar
louis_sutton
Laser Shark
Laser Shark

Posts : 191
Location : north london

Re: Valve Clearances

Post by louis_sutton on Sun 18 Jun 2017, 7:57 pm

Yeah that's the one. I can see that in my immediate future. Splendid.
avatar
sullivj
the 900
the 900

Posts : 2080
Location : Gatwick

Re: Valve Clearances

Post by sullivj on Sun 18 Jun 2017, 8:05 pm

Try tightening it slightly, before you try and undo it. You might just break the seal. I would normally suggest some plusgas, but think the rubber seal will prevent it from getting near the threads.

It may be a bit extreme, but you could remove the whole cover instead.
avatar
Jameshambleton
Moderator
Moderator

Posts : 1680
Location : Bedale, North Yorkshire

Re: Valve Clearances

Post by Jameshambleton on Sun 18 Jun 2017, 8:57 pm

Loads and loads of heat, a hammer and a 10mm hex on a breaker bar helps. A very quick impact on the end of the breaker bar will do one of two things, brake it loose or round the inner head out. 

With one of mine I ended up welding some spots around it to heat shock it and it had a very little affect.

Also what sully said
avatar
ANDYC
the 900
the 900

Mechanic
Posts : 684
Location : Windsor

Re: Valve Clearances

Post by ANDYC on Sun 18 Jun 2017, 9:23 pm

Take the whole alternator cover off and get a spare gasket just in case.
Much easier and cheaper than trying to get the inspection cover off.
avatar
Fair Weather Rider
Barry Sheene
Barry Sheene

Posts : 88
Location : Tenbury Wells

Re: Valve Clearances

Post by Fair Weather Rider on Mon 19 Jun 2017, 8:26 am

@ANDYC wrote:Take the whole alternator cover off and get a spare gasket just in case.
Much easier and cheaper than trying to get the inspection cover off.
Very sensible, less aggro.
avatar
louis_sutton
Laser Shark
Laser Shark

Posts : 191
Location : north london

Re: Valve Clearances

Post by louis_sutton on Mon 19 Jun 2017, 10:59 am

Eminently sensible. I started gently with a breaker bar (plus Allen socket bit) and just a touch of heat. Neither that or a manual impact driver made any difference, but the Allen bit is starting to shift in the cap. So, excellent idea. The case will come off. Colour me ignorant-will that need an oil drain?
avatar
Jameshambleton
Moderator
Moderator

Posts : 1680
Location : Bedale, North Yorkshire

Re: Valve Clearances

Post by Jameshambleton on Mon 19 Jun 2017, 11:12 am

@louis_sutton wrote:Eminently sensible. I started gently with a breaker bar (plus Allen socket bit) and just a touch of heat. Neither that or a manual impact driver made any difference, but the Allen bit is starting to shift in the cap. So, excellent idea. The case will come off. Colour me ignorant-will that need an oil drain?

If you can keep the bike upright on its main stand then you will get a small amount of oil loss but nothing more than 100ml at best. The majority of the oil will be in the sump. The stator is oil fed by the oil pump in the lower two holes on the bottom of the crank casing, which you'll see once you've removed the cover.
avatar
louis_sutton
Laser Shark
Laser Shark

Posts : 191
Location : north london

Re: Valve Clearances

Post by louis_sutton on Mon 19 Jun 2017, 11:33 am

Awesome, thank you. I've never really had the cb engine apart as it's my daily ride-whereas the cx non runner I bought is in as many bits as an engine can be!

Sponsored content

Re: Valve Clearances

Post by Sponsored content


    Current date/time is Wed 28 Jun 2017, 2:45 am