Why do singles need a de-compressor and twins don't?
I couldn't kick my 16ms through compression, but had no problem with my m31 ..
Singles v Twins
- Taid
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Re: Singles v Twins
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Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
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Re: Singles v Twins
With a twin you only have half the engine on the compression stroke at any one time whereas with the single you are trying to compress the whole lot in one go, as a 75 year old with RA I can still manage the 650 twin but the single I have to pull on to the stand to kick over even with the decompresser. I also have a 750cc Bonneville which just about beats me to turn over, never liked it anyway.
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Re: Singles v Twins
Yep. Plus most singles have a far longer stroke and much heavier flywheels which need to be stirred into action (with the 'long swinging kick') as well as/before overcoming the compression. I see most twins being started with little more than a prod on the k/start.
'There is a tide in the affairs of men
Which taken at the flood............'
Which taken at the flood............'
- Taid
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Re: Singles v Twins
It is only half the engine, but on the 650, that's 325cc, compared to 350 on the 16ms ..
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Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
Now sold ... 1956 AJS 16MS Bitsa .. HSU 414 .. rebuilt/re-registered 1987
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Re: Singles v Twins
Blimey, g5wqian must be a bit of a wimp at 58 seeing that he’s finding kicking over his Model 30 over to start not so easy as it used to be.
At 88 I’m still starting my Model 31 and back in September did 500 miles over five days on the VMCC Cornwall Touring Week event. My problem nowadays however is loading the bike on the trailer and appreciate help in loading the bike.
At the moment the bike is not on the road due to the Cornish Piskies attacking the 64 year old rectifier and wrecking the battery so am now in the process of updating to 12 volts. MikeM.
At 88 I’m still starting my Model 31 and back in September did 500 miles over five days on the VMCC Cornwall Touring Week event. My problem nowadays however is loading the bike on the trailer and appreciate help in loading the bike.
At the moment the bike is not on the road due to the Cornish Piskies attacking the 64 year old rectifier and wrecking the battery so am now in the process of updating to 12 volts. MikeM.
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Re: Singles v Twins
At a mere 70 I have no problems kick starting my Model 31. Mind you, there is a reasonable amount of weight coming down on the lever each time... I blame it on Devon having stronger gravity than average, due to all that granite and stuff. I do find it easier to start it on the centrestand though - not because I can't start it when astride the bike - I can, but I usually manage to catch the inside of my leg on the oil filler cap at some point, and it hurts!MikeM. wrote: ↑Thu Nov 16, 2023 9:18 pm Blimey, g5wqian must be a bit of a wimp at 58 seeing that he’s finding kicking over his Model 30 over to start not so easy as it used to be.
At 88 I’m still starting my Model 31 and back in September did 500 miles over five days on the VMCC Cornwall Touring Week event. My problem nowadays however is loading the bike on the trailer and appreciate help in loading the bike.
At the moment the bike is not on the road due to the Cornish Piskies attacking the 64 year old rectifier and wrecking the battery so am now in the process of updating to 12 volts. MikeM.
Malc
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Re: Singles v Twins
They say " two heads are better than one " but I like one of each !
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Re: Singles v Twins
Singles for me.
Only one of everything to go wrong and plod along nicely
Only one of everything to go wrong and plod along nicely