GS Basic Kalahari - some advice needed

Berin

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Hi chaps, as previously discussed Mrs Berin has entered the murky world of Airhead ownership with a GS Basic Kalahari. It had some work done about 4 years ago, including a service by NOG but has more of less stood since then.

After draining and changing the fuel and giving the carbs a bit of a clean, it started and ran fine, but with an odd noise somewhere in the region of the timing chain cover. We shipped the bike up to Steptoe for a service and fettle, and Steptoe can hear the noise but not identify it. He has noticed the timing chain cover has been off at some point as it's sealed with black goo, but rather than start to delve deeper and find what what may be more major work needed, he's recommended we try to find someone who might be able to identify the noise and provide an idea of might be needed.

Can anyone offer any advice or help please? We're in South Oxfordshire, but I've I can put it in a van if someone would be kind enough to have a listen, and I also have a sound recording where the noise can be heard

:thumb2 hopeful!


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Might be worth giving Andrew Sexton a call 01608 730111 he has been building and tuning airheads for years.
North Ox/ Glous area.
 
From the history which look pretty complete I think it’s done around 55,000km. Can’t find a way to post up the sound clip up, but as someone suggested above maybe I can do a video with sound, when I get it back from Steptoe
 
Brill,:confused::confused:
Are you sure your not randomly tapping a screwdriver on the fins:D
Bent pushrod perhaps?
Tapping on the side of the tube or head as it spins.
Can’t think of much in the front case that could make a noise like that
 
Brill,:confused::confused:
Are you sure your not randomly tapping a screwdriver on the fins:D
Bent pushrod perhaps?
Tapping on the side of the tube or head as it spins.
Can’t think of much in the front case that could make a noise like that

So, it is a “noise” then?

We did have a quick look at pushrods, but only to check they moved not for straightness.
 
What did Neil recon to the the clearances and end float?
It’s definitely not a normal noise,
Hard to tell with mono sound as you cannot tell much with regard to direction or anything else.
Without getting up close and personal with the bike ,the only thing I can think that would make a randomly timed noise like that would be a bent push rod,anything else pretty much would be regular and would relate to engine speed.
A bent pushrod COULD be making contact randomly with the side of the tube or head as it comes under load,as the rod and follower is turning, because it does not sit centrally over the cam lobe,
Hope this makes sense.
 
Try running the bike with the rocker covers off - you might be able to see something, and at tickover you will be able to to check the valve clearances by feel too.
It is probably not going to go away by itself , so worth finding what it is before it gets worse and does some serious damage.
 
As boff suggests,
It needs investigating,sooner rather than later.
My other thought was,,,you mentioned the front case had been off,
Maybe someone has fitted a timing chain and the retaining clip has come off,
It could be the split link backing out of the chain and catching on the crankcase:eek:
I’ll put money on it being down to well intentioned human tinkering.
Some of the stuff I come across on the old bikes just makes me wonder:comfort
 
If its a pushrod interfering with a tube you can easily diagnose that - run the engine and use a screwdriver tip on each tube and the other end on your ear (or better still an automotive stethoscope) and you will hear which one is causing the issue.

My money tho, (as it sounds to my ear like the noise is at half engine speed and thus valve train related) is on something amiss in the timing chest given that there is evidence of meddling - seeing "black goo" or any other unnecessary sealant witness marks is nearly always a bad sign, classic marks of the unskilled home mechanic. I reckon a timing chain replacement not correctly done.......

Pull the front cover off, and run it again, might be able to hear the front area a bit better - also just check the alternator bolt is tight while you are there, tho I suspect Steptoe has already eliminated any obvious faults under the front cover like that....
 
I read recently about airhead engine noises and came across a guy in the states who had an annoying noise on I think his ST80.

He went through everything as did an airhead expert, think it was a tapping sound. If you do a search I'm sure you'll come across it, off memory it transpired that the fly wheel studs or some such thing had elongated and this caused a constant clonking on the engine casing .

Just saying ...:D
 
Thanks for all the help and comments everyone, I will ponder further


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I'd be having a look at the timing chain.

ps. If you run it with the rocker boxes off, it'll chuck oil everywhere.
 


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