G2 contact breaker end play
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G2 contact breaker end play
Hi all,
another day another challenge!!
we have today tried to time the G2 - to no success - due to the advance retard assembly catching/touching the back of the contact breaker baseplate.
ok - we have a small amount of in/out end float on the camshaft(which obviously drives the taper) - and the contact breaker plate sits nicely in its little register(I am checking to see if its flat / not bowed in any way - but seems pretty flat).
we line up the bobweights as per book and then I noticed that the advance retard spring posts are perilously close to the back plate , leaving tiny little witness marks at the back.
clearly can't leave it like that
I am trying to upload some pics for you to see - have I the right parts?? we just don't know if the parts are correct .
apologies for pics - first time I have done this !!
thank you for any suggestions
updated - we've had the camshaft housing off the engine to check inside - nothing looked abnormal - what sort of end float is there please in/out on the camshaft and is there meant to be a shim to control it please - I think we had about 1mm maybe in/out
another day another challenge!!
we have today tried to time the G2 - to no success - due to the advance retard assembly catching/touching the back of the contact breaker baseplate.
ok - we have a small amount of in/out end float on the camshaft(which obviously drives the taper) - and the contact breaker plate sits nicely in its little register(I am checking to see if its flat / not bowed in any way - but seems pretty flat).
we line up the bobweights as per book and then I noticed that the advance retard spring posts are perilously close to the back plate , leaving tiny little witness marks at the back.
clearly can't leave it like that
I am trying to upload some pics for you to see - have I the right parts?? we just don't know if the parts are correct .
apologies for pics - first time I have done this !!
thank you for any suggestions
updated - we've had the camshaft housing off the engine to check inside - nothing looked abnormal - what sort of end float is there please in/out on the camshaft and is there meant to be a shim to control it please - I think we had about 1mm maybe in/out
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- Posts: 113
- Joined: Sun Jan 27, 2019 8:52 pm
- Location: Dorset
Re: G2 contact breaker end play
Resolved
The bobweights were on back to front and inside out!
Unbeknown to us , but it didn't beat us !
The bobweights were on back to front and inside out!
Unbeknown to us , but it didn't beat us !
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- Location: ABERTAWE UK
Re: G2 contact breaker end play
Nothing worse than back to front bob weights, good you found the problem tho.
Colin
Colin
only dead fish go with the flow
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Re: G2 contact breaker end play
cheers
good fun this !!!!!
good fun this !!!!!
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- Posts: 113
- Joined: Sun Jan 27, 2019 8:52 pm
- Location: Dorset
Re: G2 contact breaker end play
Is there please a particular amount of end float of the camshaft please??
We had - what seemed a fair bit - of end float but no shims in the diagram shown
it would certainly be nice to know an acceptable end float figure or just not to worry!!
We had - what seemed a fair bit - of end float but no shims in the diagram shown
it would certainly be nice to know an acceptable end float figure or just not to worry!!
- Duncan
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- Location: HAMPSHIRE UK
Re: G2 contact breaker end play
If there is no specific information available the army service sheets are a possible guide: http://archives.jampot.dk/book/Workshop ... ndards.pdf
- Ozmadman
- Posts: 2651
- Joined: Wed Dec 14, 2011 1:02 am
- Location: ESSEX UK
Re: G2 contact breaker end play
Different bike though.Duncan wrote:If there is no specific information available the army service sheets are a possible guide: http://archives.jampot.dk/book/Workshop ... ndards.pdf
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
- Ozmadman
- Posts: 2651
- Joined: Wed Dec 14, 2011 1:02 am
- Location: ESSEX UK
Re: G2 contact breaker end play
There are no shims fitted. I fitted a new bush in my engine casing when I rebuilt my engine and with the bush flush with the casing there wasn't any end float as far as I can rememberRichard Hyatt wrote:Is there please a particular amount of end float of the camshaft please??
We had - what seemed a fair bit - of end float but no shims in the diagram shown
it would certainly be nice to know an acceptable end float figure or just not to worry!!
Paul
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
1960 Model 8
1974 Yamaha RD250B US Model 6 speed
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- Joined: Sun Jan 27, 2019 8:52 pm
- Location: Dorset
Re: G2 contact breaker end play
thank you for the suggestions - no shims fitted , we'll live with what we have , probably 0.5 - 1mm float .
by the time the oil is in there it'll hopefully quieten any float.
I suppose also , that any float will allow the followers a varying path over the can lobes.
thank you
by the time the oil is in there it'll hopefully quieten any float.
I suppose also , that any float will allow the followers a varying path over the can lobes.
thank you
- Duncan
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- Joined: Thu Jul 10, 2003 1:00 am
- Location: HAMPSHIRE UK
Re: G2 contact breaker end play
But still a sound starting point if you have no other information to guide you, they are both pushrod singles made by the same manfacturer.Ozmadman wrote:Different bike though.Duncan wrote:If there is no specific information available the army service sheets are a possible guide: http://archives.jampot.dk/book/Workshop ... ndards.pdf
In my opinion, if you run with 1mm ~40thou you will become aware of some cam noise as it slaps to and fro, if you search the history on the forum there will be discussions about it.