Sprag Clutch mmm!

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Wired up 95% of my bike, and thought I'd try the starter motor, I was unable to test it before as the live feed wire to the button wasn't there. Pressed button and I got a good whirring noise but no engine movement. I thought that it was maybe the sprag clutch as that seems to be a favourite failure in this dept. with a big payout to fix. Off with the primary cover, try it again and everything is spinning... except the engine! Ah well better have a look. I off with the outrigger plate and gear and out with the sprag clutch, noting which way it all came out. The sprag is one of the new 18 piece clutches and looks brand new. I had a look in the parts book and manual to make sure all the bits were there, they were, but the sprag looks to have been fitted the other way round!, so I tried to fit it as per book, put it together again, pressed button and got a half turn of the engine, (I have still to put on the welding cables and still using old cabling), I then took it apart again turned the sprag back to the way it was and tried again... everything spinning but the engine!
It looks like the sprag clutch was fitted the wrong way round? Is this possible ? I hope so as it will save me some money which would help thanks to Her Majesty's Customs charging me £30 for my Tri-sparx ignition this morning!!! It was fitted with the bigger edges facing out the way towards the gear, also I take it that the inner washer is fitted with it's flat back to the engine and it's protruding lip towards the gear?
A number of you are using AGM batteries, what size do you use?
Thanks
 
Yes you can fit it the wrong way around. I have taken this paragraph from Old Britts

To verify that you have the sprag bearing correctly fitted and verify that the sprag bearing is working correctly, place the above assembly in your hand holding on the drive sprocket. You should not be able to turn the crank gear counter-clockwise, which is the direction that the starter motor turns this gear. You should be able to freely spin the crank gear clockwise. There will be some drag on the crank gear when rotated clockwise, but it should turn freely. If the crank gear does rotate counter-clockwise and does not rotate clockwise, you have the sprag bearing in backwards. If the crank gear rotates in both directions or does not rotate in either direction, your sprag bearing is probably bad.

If you go to this link;

http://www.oldbritts.com/ob_start.html

Scroll down to and click technical articles, then scroll down to Gearbox..... and click on "Pictorial help with installing the E-start starter gear train," the above paragraph is included.

Hope this helps.
 
Reggie said:
Yes you can fit it the wrong way around. I have taken this paragraph from Old Britts

To verify that you have the sprag bearing correctly fitted and verify that the sprag bearing is working correctly, place the above assembly in your hand holding on the drive sprocket. You should not be able to turn the crank gear counter-clockwise, which is the direction that the starter motor turns this gear. You should be able to freely spin the crank gear clockwise. There will be some drag on the crank gear when rotated clockwise, but it should turn freely. If the crank gear does rotate counter-clockwise and does not rotate clockwise, you have the sprag bearing in backwards. If the crank gear rotates in both directions or does not rotate in either direction, your sprag bearing is probably bad.

Hope this helps.

Hi Reggie , thanks for that, I tried it as you said and it turns clockwise without any problem but does not turn anti clock wise... Brill!!
Just another little something done 'not quite right' by the previous owner!!!!
The sprag and both the gear and sprocket have no marks at all on them and look fairly new, that in itself gave me a clue that things might not be quite right. Anyway on with making the new starter cables and possibly getting an AGM battery.
Thanks again
Robert
 
rbt11548 said:
A number of you are using AGM batteries, what size do you use?

It's the amount of CCA's that are important (Cold Cranking Amps) rather than actual size.

I've been using a Westco YB14L-A2 AGM (190CCA) battery on my Commando for the last two years, bought from Tayna.

http://www.tayna.co.uk/YB14L-A2-Westco- ... P3385.html

Before that, an Odyssey PC545, although the PC545 had to be stood on end to enable it to fit into the MkIII battery space, but that's not a problem for an AGM battery.
 
I believe that the "14" indicates Amp Hours. All similar batteries that cross reference should have a "14" in the code.
 
Quick hijack since we're on the topic.

Any kind of asembly lube need to be used on the needle bearing when putting the sprag assembly back together?
 
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