One for Spooky?

[Itsme]

Spooky or anyone else who might like to chip in. And before you read on I know there's no real answer and I am just worrying.

Rufus - as you know I have a new (to me) GN250. To me it just sounds a bit more top-end rattly than the one I had from you. I checked that the cam chain tensioner was working ok and it seems to be. I checked the valve clearances and they were all set to zero! I trawled the interweb and came up with 8 thou inlet and 12 thou exhaust which I set them to. It certainly sounds no worse and no better but does seem to be running better.

The black one had a 'sporty' silencer whereas this one is standard so maybe I never noticed how rattly it was.

I guess I am asking have you ever noticed that some GNs are more rattly than others?

I love the wee beastie but find myself looking longingly at the CBF which is still in the garage and which was whisper quiet. Maybe I just need to alter my expectations a little?

Cheers chaps.

Spartacus

[themoudie]

Oh Thracian gladiator!

If the tappets were THAT TIGHT  "I checked the valve clearances and they were all set to zero!", I am wondering what the valve seats might look like, or if the piston has been touching the valves! 

From what I can find your 0.20mm (0.008") inlet and 0.30mm (0.012") exhaust were quoted on more than one site, but I think that the quoters were getting their mm and inches in a fankle. Then I found an online pdf manual for a GZ250GN that looks very similar to a 250GN. Tell me I'm wrong!

"Valve clearance (when cold):
IN. : 0.03-0.08 mm (0.001-0.003 in)
EX.: 0.08-0.13 mm (0.003-0.005 in)"

N.B. THIS IS 0.003" for the inlet and 0.005" for the exhaust that is a lot tighter than you have them now! But, nearer were I would expect the clearances to be on a "soft" cam. I wonder if somebody tried to set the tappets with the engine not set at T.D.C?    Whatever? I wouldn't run it before I had delved into it's guts above the crankcases or got my money back from the "dealer"!

This is the link to the online pdf: Suzuki-Gz250_manual.pdf

I would suspect top end wear, piston slap and or a little end making a racket. So head off, barrel off and see what you have got. May be time to claim "Goods unfit for purpose"! 

Sorry to be a pain in the Horlicks. I can only hope that the chariot is not that badly damaged and I am not Erebus! 

Good health, Bill

[Itsme]

Hi Bill

Many thanks for the research and the info, not to mention the classical references!

I am going to have to do some further investigating that much is clear, and to be honest I was already thinking that way. At least the GN isn't a complicated wee beastie and parts seem readily available and not too pricey. I understand what you're saying about returning to the dealer but I love the GN so much I would rather just swallow any cost and do the job myself.

Let's just hope that Prometheus and not Erebus is smiling on me when I do the job!

Spartacus

[Moto63]

Ian... sorry Spartacus. I’ve still got the Austin racing exhaust system that I used to run in the ktm390. Bolt than on to the GN, you certainly won’t hear any rattling from it then. 🤣😉👍
Cheers Michael

[Itsme]

Ian... sorry Spartacus. I’ve still got the Austin racing exhaust system that I used to run in the ktm390. Bolt than on to the GN, you certainly won’t hear any rattling from it then. 🤣😉👍
Cheers Michael

Ha ha, maybe that and a thicker helmet!

Spartacus

[Itsme]

Hi Guys

I had a good think about what Bill said and decided to email the dealer, Churchill Motorcycles. I didn't complain just let them know what was happening. Within 20 minutes I had a reply saying they are picking the bike up next Monday they will take it away and mend it. Now that is good customer service.

Spartacus

[Steve Lake]

i know i'm an old cynic, but, if they are that good a company ... why din't they pick this up on a pre sales check?? .... they may well sort out the tappets ets... but will they sort out the source of the noise ??  ...

[themoudie]

?

?? ?? ? ?? ?? ?? Calchas ?? ? ?? ?? ?? ?? ?? ?? ? ?.
? ??, ?

It would appear that the Greek alphabet screws up the code on the forum!    My apologies, no harm intended!

And for those mortals not involved in Greek mythology, including me, this is the English translation:

Hello Spartacus,

I tend to agree with Calchas Lake and will keep my powder dry until you have the repaired chariot returned.
Good health, Bill 

[CrazyFrog]

Hi Guys

I had a good think about what Bill said and decided to email the dealer, Churchill Motorcycles. I didn't complain just let them know what was happening. Within 20 minutes I had a reply saying they are picking the bike up next Monday they will take it away and mend it. Now that is good customer service.

Spartacus

That's good news Ian. Hope they get it sorted...

[Moto63]

I’ve got that zorst waiting Ian 😉😉👍