Engine Mounts Offset Cones

Posted:
Sat Apr 04, 2020 4:32 pm
by St George
Out of boredom I have taken my good engine out of my SIL to test my spare tuned engine. When fitting the new motor I fitted new off set cones because I had them. I then tried to fit the new mounting bolt, it fitted snug in the silent block but no way will it fit in the cones. I ended up fitting the old cones and mounting bolt. Was there different sizes in this department, thanks.
Re: Engine Mounts Offset Cones

Posted:
Sat Apr 04, 2020 6:53 pm
by ULC Soulagent
I assume it should be the same across the board. Probably the cones have not been drilled out properly. Where did you get them from? If from a reputable source then contact them or send them back
Re: Engine Mounts Offset Cones

Posted:
Sat Apr 04, 2020 8:13 pm
by St George
Thought so, came with a basket case and now re-cycled. Used to walk to Kegra to get my bits : ( Keep safe. )
Re: Engine Mounts Offset Cones

Posted:
Sat Apr 04, 2020 11:16 pm
by Warkton Tornado No.1
You probably just need to open the bore back to size just by jamming a screwdriver down the splits. It's the same principle as getting the rear hub cone on & positioned on the splines.
OEM engine cones were made of a much better steel that would spring back to shape.
If you do fit the eccentric cones, I would especially advise a good Copaslip lubricant be used, which is true of all cones IMHO.
Re: Engine Mounts Offset Cones

Posted:
Wed Apr 08, 2020 12:24 am
by coaster
Warkton Tornado No.1 wrote:.......If you do fit the eccentric cones, I would especially advise a good Copaslip lubricant be used, which is true of all cones IMHO.
Copper slip on the bolt but the cone to frame joint needs loctite bearing retainer otherwise they WILL move
Re: Engine Mounts Offset Cones

Posted:
Sat Aug 27, 2022 11:04 pm
by TonyB
I came across this thread whilst researching engine mounts as I am currently in the process of replacing the solid mount on the kickstart side of my Italian GP in an effort to reduce the amount of engine vibration being transferred to the frame.
I would have merrily just replaced the solid mount with a Scootopia one, until I came across this on the CamLam web site:- "Please note Italian/Indian diameters for engine bars and mounts are different. Italian mounts and bars are designed to be 15.9mm, so you need to use a Italian engine bars with Italian mounts. Indian ones are meant to be 16.2mm, so again Indian mounts, and stainless steel bars are meant for each other"
I mention this here as, if this is the case, it might be the reason why your SIL engine bar wouldn't go through your off-set (Italian?) cones.
If this is the case, then I guess that, if you fit SIL engine mounts, you will need a SIL engine bar and SIL engine cones.
However, a further search revealed a post which included original factory drawings of Italian engine mounts. These showed the internal diameter of the bush in the centre of the mounts as 16mm. I have a collection of various engine mounts and the inside diameters of all of them are larger than 16mm, which means that a 16mm engine bar is loose inside the bush, to a lesser or greater degree.
I originally fitted my TS1 engine with the brilliant Casa flat-sided bar and off-set cones but, even though the flat-sided engine bar is a snug fit in the off-set cones, it's diameter is less than 16 mm, so it is actually the loosest one in the engine mounts.
Sticky doesn't cover this in his excellent book and none of the dealer web sites that I looked at give any dimensions of engine bars/cones/mounts, so my solution is, I think, to pick the engine mount which has the bush with an internal diameter nearest to 16mm, go back to using my 16mm engine bar and replace the Casa ones with (hopefully) off-set cones with 16mm holes.