Gearbox oil

Information relating to the Matchless G2 or AJS Model 14 250cc Lightweight
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Woodland
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Gearbox oil

Post by Woodland »

Hi Guys, what type of oil should I be putting into the gearbox? Is it the same as the engine oil?
Please advise
Gary
56G80S
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Re: Gearbox oil

Post by 56G80S »

You might find this interesting:

https://www.jampot.com/article_read.asp?id=11

Personally, I stick with SAE50 or whatever I'm putting in the engine as per the original specification AMC, Burman B52 and later CP boxes. Different on the earlier version of CP Burman boxes of which IKBA (except that they were grease filled and a some people use a grease/oil mix? Others will clarify).

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dave16mct
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Re: Gearbox oil

Post by dave16mct »

I use SAE 50. Some use 90 gear oil.
Dave.
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Eamonn
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Re: Gearbox oil

Post by Eamonn »

The bike under discussion here is a Lightweight, so references to AMC, B52 and CP don't apply!

Read the details in the owners manual for your model - in the UK usually SAE30 for the engine and SAE50 for the gearbox. I've never owned a Lightweight, but I'm told it's very important to keep the gearbox oil at the correct level to ensure the gears are lubricated.

I'm sure other more experienced members will chip in after me!
Corners like a Lego man
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Re: Gearbox oil

Post by 56G80S »

There was no mention of the model or year. It is basically an AMC box from memory. I have owned a 14CSR 1966. I had to rebuild the gearbox. It is vital to keep it topped up. The round gearbox shell isn't conducive to low oil levels and I think, others will correct me, that the volume of oil isn't high - check the manual.

Johnny B
Red Gauntlet
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Re: Gearbox oil

Post by Red Gauntlet »

Manual recommends SAE50 to a level just below the inspection window, as others have mentioned it is important to keep these topped up as the clusters are at the top of the box and they will quickly ruin if the level is low, you can use EP90 (Extreme pressure) which is also SAE50 but has anti oxidant and additives to increase the high pressure abilities and reduce gear wear. If you have a bit of a leaky bike, use the EP as it has a distinctive smell so you know which oil is leaking. I have used both for thousands of miles without problems.
56G80S
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Re: Gearbox oil

Post by 56G80S »

"distinctive smell" - cat urine?

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Re: Gearbox oil

Post by shifter »

Topic is in G2 Model 14 Forum so I would think the question asked in the first case refers to the lightweight 250/350 box, I use sae 40 sometimes sae 50 depends what I have handy and always try to keep the oil level to just a little under the the bottom of inspection/filler cover.
As I recall the gearbox takes around 3 pints of oil from empty.

shifter
?
Woodland
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Re: Gearbox oil

Post by Woodland »

Thanks to all for your replies, I will now be using SAE50 for the gearbox. Just to clarify the bike is a Matchless G2 and build in 1961. I shall also ensure the oil level is topped up / maintained to the correct level.
Many thanks
Gary
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Re: Gearbox oil

Post by 56G80S »

Shifter,

I would've thought so too, had I looked in that part of the forum but I usually just click on "Active topics" and so the model and year was a mystery to me. I only read the headline.

Johnny B
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