1960 G5 Gearbox Bearing

Information relating to the Matchless G5 or AJS Model 8 350cc Lightweight
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bike63
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Location: Hertfordshire UK

1960 G5 Gearbox Bearing

Post by bike63 »

Hi, I need to replace the roller bearing for the main gearbox output shaft. The bearing I've removed is an SKF 2nu05 which has a modern equivalent of RNU205. The problem is the early bearing has a roller length of 6mm and the later replacement has rollers of 9mm which get "jammed" when assembled. Has anybody been able to obtain a bearing with the narrower rollers or been able to overcome the problem in some way.
John
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clanger9
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Re: 1960 G5 Gearbox Bearing

Post by clanger9 »

It definitely needs to have 6mm rollers as the bearing track is only 6.8mm wide.
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1989 Moto Morini Dart 350
1993 Ducati 750SS
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Duncan
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Re: 1960 G5 Gearbox Bearing

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bike63
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Location: Hertfordshire UK

Re: 1960 G5 Gearbox Bearing

Post by bike63 »

Hi Duncan/Clanger, thanks for your replies .... the picture on Jampot Spares is the same as the one I've removed and with 6mm rollers. I'm waiting to hear from them as to whether the one they sell has 6mm rollers or is simply a RNU205 with 9mm rollers and which doesn't work.
Cheers.
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ajscomboman
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Re: 1960 G5 Gearbox Bearing

Post by ajscomboman »

What doesn't help is 2 bearings with the same number but different specifications! RNU 205 has 2 different ID's and depending on what one you require the rollers are different. If you opt for the 31.5mm ID dia which is wrong for our bikes that has the 9mm rollers as the cage size is thinner. The 32mm ID has a thicker cage and 6mm rollers and is correct for our bikes. That's what I asked the suppliers to give us and hope they did. Tis a minefield getting spares.
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