Knock On's vs Bolt Ons

[Famous Frank]

Okay, I always try to remember being told, there is no such thing as a dumb question. You would think after owning one or more Lotus since 1972 I should know the answer but I don't. So here goes.

I'm about to remove knock on hubs from one Elan and install them on another. Will the knock on hubs be a direct fit on the front or is the spindle size, and or upright a different size? Would I also have to switch those parts too?

And two, I have just recently purchased a Hub Puller (thank you 1owner69elan), to remove the rear knock on hubs. What is the recommended way to remove the bolt on rear hubs without bending the hell out of them?

Many thanks, Frank

[CBUEB1771]

Frank,
The part numbers for the stub axles, uprights and bearings are different for the bolt-on and knock-on variants. The these parts for the knock-on variant have mostly 036 prefix rather than 050 so I am not sure if the larger diameter, GT6 stubs axles were adopted with the earliest adoption of knock-on hubs. However it is clear that the parts are different.

[rgh0]

The Elans and PLus 2 with knock-ons always used the larger stub axle and different bearings as used by the GT 6 / Vitesse versus the smaller diameter units used on the Spitfire / Herald for bolt on hub Elans

However I believe both stub axles fit in the same upright. There is a later upright which had a different detail around the steering arm location but the stub axle mounting was the same.

Doing this from memory so happy to be corrected.

cheers
Rohan

[gjz30075]

If both Elans are an S2, wouldn't they be the same?

[Orsom Weels]

However I believe both stub axles fit in the same upright. There is a later upright which had a different detail around the steering arm location but the stub axle mounting was the same.
Rohan

We went through this with my friends series 3, he had a miss-match of parts to work with & we found the stub axles were specific to the upright, the smaller stub axle would almost fall through the larger upright, leading us to have to find a pair of bolt on hubs to fit the larger stub axle size. The trunnion threads were knackered on the original smaller uprights, & we had thought we could simply swap the stub axles to the good uprights & use the original hubs

Regards, Tim

[gjz30075]

If I understand Frank's question, he's asking if Lotus would have changed the spindle due to being a KO car
versus a bolt on car.

edit: At first I wouldn't have thought Lotus would go to the expense of differing parts but clearly, as Russ
pointed out, the KO spindle is a different part number from the bolt on spindle, as with the upright.
Frank, I suggest taking the whole assembly, ie, assembled upright, with brakes, for the swap.

[Craven]

Hi Frank,
Definitely smaller diameter stub axle on bolt on?s, you may get away with finding a suitable pair of bearings that fit the stub axle and also fit the hub.
Bearing for knock on?s both ID & OD are different.
Ron.

[Elan45]

NO, Bolt on hubs use the smaller version of the upright, stub axle and hub, while the KO wheeled Elans use the larger version of upright, spindle and hub. At the front, the KO version of the Elan use the same set-up as the +2, but at the rear, the hubs have a different offset.

The smaller bearing bolt on setup is also used on early Sevens and all Europas and various formula cars and the 23 sports racer.

Earlier, the Eleven S2 used the upright and spindle from the Standard ten or TR 10 in North America, but did not use the hubs since the hubs were cast into the wheels The lug nuts and bolts merely hold the brake disc to the wheel/ hub. There are various iterations of the upright/ spindle/hubs up through SRs post Eleven, but all used the smaller bearings.

Roger

[gjz30075]

Roger, the +2 wasn't announced until 1967, so what is the origin of the larger parts for an S2 Elan KO, predating
the first +2?

[Famous Frank]

Now this is getting interesting. i know I made a similar swap but that was 40 years ago and I don't remember.

I won't bother looking for different bearings, etc. I'll just swap the entire upright, spindle and hub. But if you saw what they look like, that could be dubious also!!!!

Now what about the second question - what are the recommendations for removing the rear bolt on hub without warping or damaging the hub?

Thank you everyone!

Greg, good question! What was the early source?

[Orsom Weels]

Greg, good question! What was the early source?

Rohan has already answered that in the 3rd post,
"The Elans and PLus 2 with knock-ons always used the larger stub axle and different bearings as used by the GT 6 / Vitesse versus the smaller diameter units used on the Spitfire / Herald for bolt on hub Elans"

To confirm this, we used a pair Vitesse hubs to convert the larger K/O uprights/stub axles to bolt on for my friends S3.

[gjz30075]

Bingo! Missed that, thanks!

[CBUEB1771]

Bingo! Missed that, thanks!

The Vitesse went into production in 1962.

[fatboyoz]

Hi Frank,
Here is a Triumph Herald rear bolt on hub remover. Not sure if it is the same, but this is what mine looks like.

http://www.canleyclassics.com/miscellan ... lling-tool

Here is an image of a home made puller.

https://www.google.com.au/search?sclien ... 8ogGnx9lH8

If you search "Hub Puller" in the Photo Gallery of Lotuselan.net there is also a photo of a home made puller.

Happy New Year,
Colin.

Now this is getting interesting. i know I made a similar swap but that was 40 years ago and I don't remember.

I won't bother looking for different bearings, etc. I'll just swap the entire upright, spindle and hub. But if you saw what they look like, that could be dubious also!!!!

Now what about the second question - what are the recommendations for removing the rear bolt on hub without warping or damaging the hub?

Thank you everyone!

Greg, good question! What was the early source?

[Plus2cabby]

Hi Frank

I have fitted bolt on hubs to my 1970 plus 2
Used vittesse on the front
B_by elan hubs on the rear , these require a 5 mm spacer to clear my 51/2 x 14 minilite replica wheels with 175/65/14 tyres on , I have full spyder double wish bone rear suspension set up.
When it came to removing the old rear hubs I applied the puller , with "reasonable" pressure went in for a brew,
re-filled kettle boiled and poured contents over rear hub and hey presto it fell off !
Couldn't believe my luck , repeated for other side and same result .

Good luck

Mark