Author Topic: Replacing quadrant  (Read 794 times)

Offline a101960

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Replacing quadrant
« on: 06.07. 2017 13:23 »
Before I tear everything apart, I need some advice. I want to change the gear change quadrant. Both the Haynes manual, and the BSA instructions talk about pressing out the gear change spindle bush which I assume is item 42 on the drawing, and the using a  bolt to extract the spindle item 45. Neither manual explains how this is done. Can anyone tell me what is involved please? Will the bush need to replaced once it has been removed? I have bought a new quadrant and gear selector plate item 39. The bolt is specified as being ¼  26 TPI,  but what thread is it? BSF or BSC? I just want to ensure that I have everything to hand (parts and knowledge) before I attempt to carry out this task.
John

Online JulianS

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Re: Replacing quadrant
« Reply #1 on: 06.07. 2017 14:30 »
I use a suitable spacer (I use suitable sockets) on both sides and press it out using a vice. Done carefull you should not damage it but if you do burr an inside edge it should easily dress.

The spindle part 45 on the illustration is usually an easy sliding fit. Either a 1/4 x 26tpi BSF oy ccycle thread bolt/screw/tap will fit. There is very little difference between the 2.

Then press the bush back in.

My advice is to carefully examine the selector fork 67 3441 part 39 your illustration. If the quadrant is worn this will probably also be worn.

Offline Topdad

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Re: Replacing quadrant
« Reply #2 on: 06.07. 2017 14:47 »
If the part number reffered to by julian is number 39 on the exploded view ,i've got a brand ne w one if it would be any good to you ,regards Bob.
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Offline a101960

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Re: Replacing quadrant
« Reply #3 on: 06.07. 2017 15:04 »
Quote
If the part number reffered to by julian is number 39 on the exploded view ,i've got a brand ne w one if it would be any good to you ,regards Bob.
Bob thank you for your generous offer, but I have already bought a new one. I am just left with the inner cover gasket to get. Julian thank you for explaining what needs to done to get the bush out. Lack of detail seems to be endemic in many workshop books. Perhaps if I was more mechanically minded the methods would be more intuitive.
John

Offline duTch

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Re: Replacing quadrant
« Reply #4 on: 06.07. 2017 17:10 »

 May be worth noting the layshaft endfloat before you strip it, just so you can compare it to after a new gasket which may or not be different..
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Offline a101960

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Re: Replacing quadrant
« Reply #5 on: 06.07. 2017 17:47 »
Quote
May be worth noting the layshaft endfloat before you strip it, just so you can compare it to after a new gasket which may or not be different.
Thanks for the tip. I will do that, it did enter my mind that there will most likely be a difference in gasket thickness. One more thing that I need to check out. The kickstart ratchet lock washer. My parts book says it is p/n 67-3164. Straight forward enough until I looked at the Draganfly website where it lists several diiferent part numbers. Is the p/n I have shown the correct one?


Online muskrat

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Re: Replacing quadrant
« Reply #6 on: 06.07. 2017 21:15 »
G'day a101960.
67-3164 is correct for the A7/10 plunger and swingarm.
Cheers
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Offline duTch

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Re: Replacing quadrant
« Reply #7 on: 06.07. 2017 22:39 »

 I can only see same three (67-3164) numbers for; Plunger A Group, S’arm A/B Group, C10/11/11G -4 Speed;
  And # 29-3585 for C10L/12 4 Speed
   
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia