Ajs 16m

Helpful information and requests for assitance and advice
got2BaSBT
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Location: Staffordshire UK

Re: Ajs 16m

Post by got2BaSBT »

Thanks again chaps, I'l keep you posted on what I find.
One other thing, is it safe to use unleaded on these if I'm only chugging around country lanes on it?
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Group Leader
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Re: Ajs 16m

Post by Group Leader »

I have been in my '53, doing exactly that, and 5800 miles later things seem good :D

Alan
1953 AJS 16MS, 1939 BSA 250 and a 1/3 scale Sopwith Triplane but that's another story ..... :lol:
SPRIDDLER
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Re: Ajs 16m

Post by SPRIDDLER »

got2BaSBT wrote:One other thing, is it safe to use unleaded on these if I'm only chugging around country lanes on it?
A common concern. Have a read of the latest thread from a couple of weeks ago........

http://www.jampot.com/forum/viewtopic.p ... t=additive
'There is a tide in the affairs of men
Which taken at the flood............'
got2BaSBT
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Location: Staffordshire UK

Re: Ajs 16m

Post by got2BaSBT »

Thanks again for all your info and help folks, turns out the exhaust valve cap had dislodged and then fallen off. That explains the temporary loss of compression and then the massive valve clearance.
I can easily sort it but how did it happen. I'm thinking something must of temporarily prevented the valve from closing....but I was only doing 50 in top at the time, surely that wouldn't valve bounce it!
Maybe it sucked in a wasp😃
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clive
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Re: Ajs 16m

Post by clive »

Most likely reason a temporary seizure of the exhaust valve. This can sometimes be caused by build up of carbon on the tulip part of the stem.
clive
if it ain't broke don't fix
Mick D
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Re: Ajs 16m

Post by Mick D »

Hi

It could be the result of weak valve springs coupled with debris as Clive suggests.

I haven't checked whether replacement springs are available but if they are, now would be a good time to have the head off, inspect the springs and replace them if required. Couple this with a de-coke and rest easy for the future ;)

Regards Mick
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ajscomboman
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Re: Ajs 16m

Post by ajscomboman »

Mick D wrote:Hi

It could be the result of weak valve springs coupled with debris as Clive suggests.

I haven't checked whether replacement springs are available but if they are, now would be a good time to have the head off, inspect the springs and replace them if required. Couple this with a de-coke and rest easy for the future ;)

Regards Mick
It could be, or maybe it's just a once only happening. I'd be tempted to just put the cap back on and reset the clearance and see if it runs sweetly for a while. If it was running nicely till the event then it's got to be worth a try.
56G80S
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Re: Ajs 16m

Post by 56G80S »

I'm with Rob Swift on this.

Sometimes one off things happen.

Our two years old Bosch washing machine had run perfectly from new. Quiet, no vibration even at 1400 rpm spin. Two months ago Linda called me. The washing machine had bounced around, and sounded like something broke. She'd switched off as soon as possible.

Dismantled and saw that the housing for the pull out conditioner etc drawer was broken. Replacement expensive new and only whole unit on sale on Ebay. undo some hoses and screws, thorough clean/degrease, Gorilla glue and replaced. All good. No more incidents.

Why?

No idea.

Johnny B
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clive
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Re: Ajs 16m

Post by clive »

Are you suggesting an AJS 16 M runs like a washing machine Johnny?
clive
if it ain't broke don't fix
JDFS79
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Re: Ajs 16m

Post by JDFS79 »

Must had been a virus!!!( Worldwide) I had the same problem in my G3, last Sunday after a 50km run with some hills somewhere in the middle and a 37 degrees temperature when I was almost arriving home the bike lost power as the throttle didn't respond , I thought I was running out of fuel !! I manage to arrive home slowly and park the bike I check the tank and it was half !!! The day after I try to get the bike started but no go !!! The compression was definitely less than normal,( the bike usealy starts first kick ), so I searched in the forum for the possible solution , as it was mentioned here, all the tips for the alloy head ( 1952 G3 ls) , no luck I have to go deeper Head off :headbang: - I have changed spark plug , check valve clearance I check if the magneto produce current ( little finger in the slip ring and kick the start :D )It was ok!!!
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