Fitting BGM Engine Mounts

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TheSeeker
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Hello Folks

I'm fitting some new BGM Engine Mounts. I have the correct tool and was able to remove the original narrow mounts with no problem.

Fitting the new BGM ones is a different story. I was able to get the right hand mount in with some struggle but the left has 9mm to go with no sign of it moving. I used an old engine mount as a spacer so that the nut was turning on a clean part of the bolts thread.

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I've done this several times in the past, fitting Indian GP engine mount silent blocks with no problem.

Does anyone have some advice? Using a blow lamp seems to be counter-productive as the steel of the mount stays warm a lot longer than the alloy of the engine casing. My next idea is a steel bar over the handle of a right angle socket spanner like this but I don't want to break anything.

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Cheers

Ben
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jason frost
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Bit of heat will help, I put a bit of copper slip on them and use a vice to press them in
shocky
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Just be aware ifthere to tight you might split the mount
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Adam_Winstone
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Even with the correct tool, the casing should be heated prior to removal of old and prior to fitting of new. Alloy expands faster than steel so will help massively, even if you had to wait for it all to cool and then heat again.

Heat is a must with this tool as relying on the force of the tool to push it in/out loses the interference fit of the casing. After a couple of mount changes without heat there is a good chance that the mount would be loose for subsequent changes (first hand experience of this!).

I'm your shoes I would be tempted to heat the casing, remove the mount and measure it, along with the old one, and compare the diameters. I have known oversize mounts to crack the casing... especially when mounts have been chromed and the diameter has increased slightly.

Adam
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jason frost
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Do it with the vice and copper slip and they go in, no messing, will post some pictures of how to do it ;)
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TheSeeker
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Thanks for the advice.

Got it in this afternoon using a mix of all techniques.

Image

Put some copper slip on the remaining part to go in. Bought a cheap 24mm spanner and chopped the C end off so I could put a pipe over the end for some more leverage (and without fear of breaking my ratchet). Plenty of heat each time and it slowly went in. Did it on the floor so I could put some weight on it, the trickiest part was getting into the yoga position with my feet right foot holding the other spanner down and left foot holding the gearbox end of the case down. Not a job to do alone.

Cheers

Ben
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Stampede
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Have you measured the mounts before fitting (and compared to the old ones)? As far as I know, there was a series of BGM mounts which are a little too big, which makes the fitting quite hard.
Bufficus
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If you run an open mouthed carb on the right side be sure to cover the mount with an aerosol can lid or similar. My right side BGM mount failed on the way back from Davos and made the last days ride really unpleasant. It had only been fitted 1500 miles earlier and was not protected from spitback from the carb. It may just have been a dodgy mount (I hope not at £50) pair or degradation caused by un-atomised fuel.
Tractorman
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TheSeeker wrote:Thanks for the advice.

Got it in this afternoon using a mix of all techniques.

Image

Put some copper slip on the remaining part to go in. Bought a cheap 24mm spanner and chopped the C end off so I could put a pipe over the end for some more leverage (and without fear of breaking my ratchet). Plenty of heat each time and it slowly went in. Did it on the floor so I could put some weight on it, the trickiest part was getting into the yoga position with my feet right foot holding the other spanner down and left foot holding the gearbox end of the case down. Not a job to do alone.

Cheers

Ben
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Livi- Graeme
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Is there a reason people don't put the mounts in the freezer then hear the casing and pop them in. Just asking cause it worked for me. Didn't even need the tool to pull them back in
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