Valve Clearance Guide

Forum rules
Please can you post items for sale or wanted in the correct For Sale section. Items / bikes for sale here will be removed without warning. Reasons for this are in the FAQ. Thanks
Post Reply
User avatar
CMSMJ1
Site Supporter
Site Supporter
Reactions:
Posts: 9507
Joined: Thu May 01, 2008 9:42 am
Bike owned: NC30-No9, NC27
Location: Chesterfield, United Kingdom
Re: Valve Clearance Guide

Post by CMSMJ1 » Wed Oct 23, 2013 7:16 pm

^ you change the shims...
IMPERATOR REX ANGLORUM

The V4 is the law..

NC30 - No9 > My old mate
2005 ZX10 C1H - It is a beast
KTM Duke 390 - for shits and giggles

User avatar
scubasteve
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 60
Joined: Thu Mar 01, 2012 2:18 pm
Bike owned: 2xNC30's
Location: Lincolnshire
Re: Valve Clearance Guide

Post by scubasteve » Tue Nov 26, 2013 6:55 pm

bizzle3 wrote:hi
First of all thank you viper for this detailed guide it looks simple enough to do, my question is, excuse me if i missed it in previous post (ive been through all 18 pages) what to do if your valve clearances do not match up? some people have addressed this issue but nobody has said anything about the procedure to rectify this? im worried my exhaust valve are out. :|
The arm that holds the shim in place slides to the side to gain access to it if you need to replace it. I used a magnet pen to remove it as it sits in a recess and can be tricky to get out. Best to put something down to block any passages into the engine like a few rags or foil I believe has been suggested before incase you drop the shim. Last thing you want is a shim dropping into your motor.
Bikes don't leak oil, they mark their territory.

User avatar
GeeTee
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 282
Joined: Mon Jan 20, 2014 1:27 am
Bike owned: NC30 & GSXR750K4
Location: Dartford, Kent, United Kingdom
Re: Valve Clearance Guide

Post by GeeTee » Sun Jan 26, 2014 3:21 am

I've been checking the shims on my NC30 today, and got similar results to Haydn (post #95)in that the inlets aren't far out, but the exhausts are all near top limit or over. One of the rear pots is at 0.31 on both exhausts. Mines also been used for several years as a track bike, and possibly a bit choked up judging by the sooty plugs. Question is do I adjust the shims on all the loose valves, only for them to close up prematurely after some hard track use. The shims really are a pain in the arse to check/swap, and don't want to face having to it again anytime soon. Speedo had just over 30,000km showing which if accurate isn't that high for an NC30 lump. Oil looks pretty clean too so hopefully it's had some servicing done.

Oh and I'm another one with a seized in timing cover. I rounded the 17mm hex off trying to get it undone today, so had to use a rod down plughole to find TDC, and turn engine over using back wheel. I'm going to try a full hex sochet to see if that shifts it, but guess it's been overtightened by some idiot in the past :x

User avatar
GeeTee
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 282
Joined: Mon Jan 20, 2014 1:27 am
Bike owned: NC30 & GSXR750K4
Location: Dartford, Kent, United Kingdom
Re: Valve Clearance Guide

Post by GeeTee » Wed Feb 12, 2014 10:20 am

After chatting to Rick Oliver on the phone I decided to adjust 2 inlets and 4 exhausts shims that were outside HRC specs. I'll leave the rest until it's had a bit of on track thrashing, and recheck them later in the year to see if anything has changed. Those front outer exhaust valve shims were a bitch to get at... must have taken me a dozen attempts to get them back in. The rebuild is making good progress now :grin:

carpman
NWAA Supporter
NWAA Supporter
Reactions:
Posts: 218
Joined: Sat Jul 17, 2010 9:18 pm
Bike owned: 1990 nc30
Location: Se London
Re: Valve Clearance Guide

Post by carpman » Mon Apr 14, 2014 10:17 pm

While my carbs are getting checked over I used this guide to check my clearances but I checked for my gap between the rocker arm and the cam does this make a differance ?

EvanTate
Settled in member
Reactions:
Posts: 56
Joined: Thu Oct 25, 2012 12:17 pm
Bike owned: VFR400 NC24
Location: Cape Town, South Africa
Re: Valve Clearance Guide

Post by EvanTate » Tue Nov 04, 2014 2:22 am

Pics seem to have disappeared on the NC24 guide on page 14. Is it just me or what? Does anybody have them saved still?

LightAndFast
Settled in member
Reactions:
Posts: 8
Joined: Wed Jul 29, 2015 1:04 pm
Re: Valve Clearance Guide

Post by LightAndFast » Fri Aug 07, 2015 11:56 am

Do you think a metric feeler gauge that goes up in 0.05mm increments is going to be accurate enough?

LightAndFast
Settled in member
Reactions:
Posts: 8
Joined: Wed Jul 29, 2015 1:04 pm
Re: Valve Clearance Guide

Post by LightAndFast » Mon Aug 10, 2015 9:40 am

The bike is a UK NC30.

Finally managed to check the valve clearances. The only ones that are out are front right cylinder, one inlet 0.20mm and one outlet also 0.20mm. They are only just out so I think I will leave them. All the CAM shaft lobes look perfect, no markes at all.

I found the front CAM cover very difficult to get off and could not position it back on. How do you get it past the wiring loom?

Is carburettor cleaner good do clean the gasket and mating surfaces?

Does grease keep the gasket in the groove while the cover is moved into position? Mine is quite a loose fit in the groove. I guess any grease will do.

Lower radiator looks really bad. I will search this site to see what the options are.


Post Reply

Return to “V4 - Workshop”