Throttle slide
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Throttle slide
Both my G5's have throttle slide 3 not 3&1/2 they run ok but why should someone replace the slides on both my engines with 3, I assume they should be 3&1/2 ?
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Re: Throttle slide
Hi Red check the parts book page 9 says part number 389-060 valve throttle - size 3-1/2. Carb should be 389 1-1/8 bore. My assumption is that someone may have had a performance issue and thought it was related to the throttle slides i.e mixture too weak. Larger the cutaway the weaker the mixture.
I fitted all four G5's that i have built over the years with the set up above without any issues. All were bog standard except for going up to 20T on the gear box output.
Cheers
Steve
I fitted all four G5's that i have built over the years with the set up above without any issues. All were bog standard except for going up to 20T on the gear box output.
Cheers
Steve
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Re: Throttle slide
Yes it does say 3.5 for the slide but I was puzzled as to why both had a 3 in the carb, I also noted that there was another thread that said 3 not 3.5 I shall swap it over and see what happens. Performs ok with the 3 though.
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Re: Throttle slide
My G5, a non runner had a carb on it for a 500 machine. Returned to standard setup starting and running great but.......
I'm more I interested in Rangy65s comment on "20T on the gearbox output". This G5 seems to be under geared and anything more than about 42mph is painful.
Any tips?
I'm more I interested in Rangy65s comment on "20T on the gearbox output". This G5 seems to be under geared and anything more than about 42mph is painful.
Any tips?
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Re: Throttle slide
Ok the easy way to alter the gearing is to change the rear sprocket as its a bolt on job like more modern machinery. The club spares scheme has just had some standard one's (55T) made up by a really well known sprocket manufacturer. So for the rear you need to go down on the number of teeth. I personally used B&C Express who are close to where i live in Lincs. Someone will probably know exactly how many teeth to drop down to but as a guess i would go to 52. The sprockets are made from Duraloy & hard anodised, not steel but they do wear well. You would need an old sprocket as a pattern. Villiers spares did have some different sizes as the same hubs were fitted to FB's.
Regards
Steve
Regards
Steve
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Re: Throttle slide
Looking at the 1957-1964 Matchless All Models Workshop Instruction Manual I find that the slide is listed as 3, last night I swapped it over to a 3&1/2 and looking at the cut away there is a small difference (1/32"), I will go for a run this evening and see if there is any discernible change in performance.
From the parts list however it does state 3&1/2.
I shall get a new rear sprocket for future use, I did not realise they were now available again.From the parts list however it does state 3&1/2.
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Re: Throttle slide
Road tested the bike last night 30 miles, indeed a good performance change, surprising really for such a small difference in the slide dimensions. so in conclusion 3&1/2 slide is the one to use.