The BSA A7-A10 Forum
Technical (Descriptive Topic Titles - Stay on Topic) => Gearbox, Clutch, Primary => Topic started by: duTch on 06.02. 2015 10:07
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I know this one has been discussed in depth, and haven't gone researching, so if it hasn't happened already- I found an easy fix...much better than jamming the missus's ride in the spokes.....
Yesterday I pulled off the Cush spring, usually a challenge but came off with a tap of a rubber mallet.......
Tightening was not so easy, as my clutch lets go after about 40 ft/lb, so I had beverage and would've slept on it, but I didn't get that far....
had thought of dropping the sump plate and jamming something in there, but that idea evaporated kinda easy..until.. *beer* *????*where's that lightbulb when I need it..?? *conf2* ok got it... *idea*
ok
The lower primary adjuster bolt on Plunger engines, which equates to the lower of the two rear studs holding the inner primary case on S/A engines, can be removed and replaced with a longer bolt to jam the counterweight web of the crank as it approaches @ ~20˚ATDC to tighten cush nut, or to loosen ~60˚BBDC....I think (?) depending on the crank...it was too easy
I took pictures, but can't find them now... *pull hair out*
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Not quite sure I'm in favour of that one Dutch, in my mind's eye I see possible damaged threads that have to return out through an threaded alloy casting.
Maybe I'm just having a glass half empty day
Clutch holding tool is the dogs doodahs I found
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much better than jamming the missus's ride in the spokes
rofl
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Does sound like maybe you could bend the bolt over?
I happened to be doing a similar job - removing the engine sprocket on the primary of my Sportster just a week or two back. The nut is a normal RH thread but boy was it tight. The manual did suggest coiling nylon line in through a spark plug hole on that cylinders firing stroke to give some resistance. Hanging on to the tail of the line of course. Which puts it all through the rod I suppose - and I guess they should take it.
Rather than do that I managed to make a plate to join a larger stud to one of the tapped holes in the sprocket. Took a 5 foot pole over the end of my socket T bar to get things finally moving. No sudden bang either.
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Here's the approach I last used for tightening the nut. Haven't yet had the need to test this method for loosening.
http://www.a7a10.net/forum/index.php?topic=368.msg58817#msg58817
Richard L.
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rofl
....what's that...a Viking chortle..??
Yo Bill, that was the first thing I thought of, and thought to waste a bolt and grind off the excess thread on the end, but when I screwed in the bolt to measure up (Unbrako 3/8" x 1" socket cap) I figured I'd do a test run steady, steady- started at 40 ft-lb no probs..55,60,65...before I'd even noticed- job done..no probs !
In fact I was so surprised, I did it twice to check..!!
For what it's worth, the Bolt hole is ~74mm (almost 3") radius so 65lb @ 12" i guess equates to ~264lb @ 3"...(unless I'm doing the maths wrong-mathx2 for Richard, I did it twice)
So all I can say is that this is my future preferred method, not negotiable, not even going to argue about it....try it or don't try it.
*beer* aaahh *beer*.... *smile*
Ok Richard, Yea rounded me up , I'll have a look
edit here, Richard I looked at your idea, admirable but I was expecting the cable to attach bottom-top in a X pattern on the chain (if yea kenow what I mean), so depending if tightening or loosening, the wire would be pulling against the upper (or lower) chain running in opposite direction..... but I like mine better...sorry-not *smile*
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(excuse for offtopic)
http://www.internetslang.com/ROFL-meaning-definition.asp
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If it works for you Dutch then that's the way to go
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There's always "more than one way to skin a cat". Apologies to our feline lovers.
I prefer a rattle gun, bike in gear, rear brake locked.
Cheers
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haaha...a10gf- careful, don't rofl too much or 'someone' may need that unused ride to sweep you up. *smile*
Bill and Musky- sorry that may ahve sounded a bit contentious, but that's where the mood swing took me... *conf*
Seriously though, you'd be surprised how easy it is..
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I use the piston stop method commonly called the "Indian Rope Trick "
Rope down the plug hole.
If you wistle or hum the right tune the rope will levitate out of the plug hole when you have finished and hang straight up .
Wistle the wrong tune and the carpet you are working on will lift up & fly out the window.
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Always worried I might bend a rod doing that - am I just being a gurl?
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G'day cyclobutch. Only if you need to use a 6' pipe to undo the nut. The closer to TDC when it all locks up is best, and make sure it's on compression stroke (valves closed).
Cheers
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Always worried I might bend a rod doing that - am I just being a gurl?
It's actually the recommended method by Rotax for removing clutches from snowmobile engines. It works very well, I do it whenever I need to lock up the crankshaft.