Lotus Europa Community

Lotus Europa Forums => Garage => Topic started by: dakazman on Tuesday,May 21, 2019, 10:15:44 AM

Title: New rear hub design .
Post by: dakazman on Tuesday,May 21, 2019, 10:15:44 AM
I found out his picture of hubs for sale on Instagram. I did not post it in the FS area because I cannot verify anything about it. It may show up here or has shown up all ready. Just putting it out there for comment.
Title: Re: New rear hub design .
Post by: andy harwood on Tuesday,May 21, 2019, 11:08:50 AM
They look really nice. I'd be interested in a pair!
Title: Re: New rear hub design .
Post by: LotusJoe on Tuesday,May 21, 2019, 11:28:37 AM
They certainly look beefy enough!
Title: Re: New rear hub design .
Post by: Certified Lotus on Tuesday,May 21, 2019, 12:06:48 PM
Looks like C&C created from solid block vs cast.
Title: Re: New rear hub design .
Post by: gideon on Tuesday,May 21, 2019, 12:45:35 PM
They would need to be hollow, or they'd be too heavy.  No way that I can see to do that by machining from solid.
Title: Re: New rear hub design .
Post by: dakazman on Tuesday,May 21, 2019, 01:12:09 PM
I’ll let ray to figure out how to contact him on Instagram. Definitely from Japan.
Dakazman
Title: Re: New rear hub design .
Post by: jbcollier on Tuesday,May 21, 2019, 03:57:17 PM
I hear what Mr Gideon is saying but I'm not sure I agree it necessary to have them hollow.  Yes it adds unsprung weight but not that much compared to the larger wheels and tires people are fitting these days.

I'm not interested myself as I had a spare set of mine machined out and fitted with steel sleeves.  Worked out very nicely.
Title: Re: New rear hub design .
Post by: Clifton on Tuesday,May 21, 2019, 04:44:20 PM
If someone put that much work into them, I would think they removed as much as they could on the back side for weight. My friend makes billet parts for older (S30) Z's. He removes as much weight as he can. http://www.arizonazcar.com/diffmount.html
Title: Re: New rear hub design .
Post by: lotusfanatic on Tuesday,May 21, 2019, 09:50:48 PM
very nice!

I'd be interested as they would be an improvement over aging cast hubs.
Hopefully very little weight increase?

Mark
Title: Re: New rear hub design .
Post by: andy harwood on Wednesday,May 22, 2019, 04:01:00 AM
"Yes it adds unsprung weight but not that much compared to the larger wheels and tires people are fitting these days."
I've wondered the weight difference between original period wheels, tires (tubes?) compared to new aluminum wheels, tires. Is there much of a difference? Is there a comparison out there somewhere?
Title: Re: New rear hub design .
Post by: Sandyman on Wednesday,May 22, 2019, 04:34:11 AM
Adding to Andy's comment. What is the weight difference between this aluminum hob and the original steel one? Must be lighter.
Title: Re: New rear hub design .
Post by: jbcollier on Wednesday,May 22, 2019, 05:49:33 AM
The original uprights are cast aluminum and are hollow.  They are actually very light.

Whether tires are heavier depends on their size and construction.  Generally tires with a higher speed rating are heavier.  Tires with "V" and higher speed ratings can be as much as twice as heavy as "H" to "T" rated tires.  Also remember that speed ratings are for a continuous speed.  I run "T" rated tires.  They are good for a continuous 110 mph.  I might once try to see "how-fast-she'll-go" but only briefly so there is no need for a higher rating and the extra weight.

Rims also vary widely.  My 13"x 5.5" Cosmics actually weigh more than the stock steel rims.
Title: Re: New rear hub design .
Post by: cwtech on Wednesday,May 22, 2019, 07:32:17 AM
If they are indeed solid, holes could be bored through them to reduce weight without compromising strength.

It would be interesting to see the surfaces which are not visible in the pics.  ....Weight reduction could take place from those surfaces.

Not much info given.  ...Maybe they're 3D printed plastic, painted aluminum color!   :huh:
Title: Re: New rear hub design .
Post by: andy harwood on Wednesday,May 22, 2019, 08:22:12 AM
OK, color me  curious. And, since the test subjects were readily available...
Lotus Alloy Wheel - 16.5 lbs  with Yokohama 185/60R/13/80V tire - 29.1 lbs.
Rota 15X6 minilite copy wheel - 14.1 lbs.  with Nexen 195/45Z/15/78W - 31.3 lbs.

Don't have steel wheels to measure.
So, if the carriers are solid, may add a couple lbs to the weight each?
In the real world, taking into account different spring rates and shock absorber capabilities, would 3-5 lbs. per rear axle really make a difference?

(Still, wouldn't mind having a set of those carriers)
Title: Re: New rear hub design .
Post by: EuropaTC on Wednesday,May 22, 2019, 08:35:27 AM
I've wondered the weight difference between original period wheels, tires (tubes?) compared to new aluminum wheels, tires. Is there much of a difference? Is there a comparison out there somewhere?

I haven't got the full data but this might give you some ideas. From my cars and weight on the same set of bathroom scales (!)

Elan, 13 x 4.5 steel rim, 155/80 tyre, 26lbs.
Europa, 13 x 5 Cosmic Alloy with 175/70 tyre, 28lbs
Europa, 13 x 5 Cosmic Alloy with 185/70 tyre, 30lbs (yes that's the numbers, I didn't believe it at first but they are different brands)
Europa, 15 x 6 MGF Alloy with 195/50 tyre, 36lbs.

I would imagine the Elan steel rim is going to be similar to the S1/S2 steel rims and the Cosmics, because they are slightly thinner, somewhere around the TC/TCS alloys.  But the message is that if you're fitting 15" rims even without significantly wider tyres then there's a definite weight penalty compared with standard.  When you look at the original steel wheels they weren't that bad at all, especially considering the 80 series tyres.

Brian
Title: Re: New rear hub design .
Post by: EuropaTC on Wednesday,May 22, 2019, 08:41:01 AM
You must have been typing at the same time I was Andy  :)

Your 15" wheel combination weight is good, although I know the MGF version I have is one of the heavier variants. But to comment on "would it make any difference ?", my gut feel is no. On a race car and perfect flat surfaces maybe, but on a road car with potholes, not so much.  It wouldn't worry me anyway.

Lotus moved from Alloy hub carriers on the Elise to steel ones, from the ceramic/alloy discs to steel discs and added a bunch of weight to every corner but no-one complained that the cars handling was wrecked did they ?

Brian
Title: Re: New rear hub design .
Post by: BDA on Wednesday,May 22, 2019, 10:07:11 AM
I agree with you, Brian. The amount of extra weight of a solid upright might have some significance on a race car, but on a street car, I doubt anybody would be able to tell the difference, if there is any.

I also seem to remember that somebody had a set cast (I thought he was on this forum but I couldn't find it quickly) and if I remember, he said the weight difference wasn't much.

While looking for the aforementioned custom cast rear uprights, I found this post that implies that Richard at Banks has either new or reconditioned uprights for sale (http://www.lotuseuropa.org/LotusForum/index.php?topic=2930.msg28302#msg28302). They certainly look nice and might be worth a look.
Title: Re: New rear hub design .
Post by: andy harwood on Wednesday,May 22, 2019, 10:54:50 AM
Brian,
I wouldn't have thought there would have been a 2 lb difference between the original Lotus alloy and the Rota. Quite a bit of difference in your 15 inch MGF alloy and the 15 inch Rota I weighed.
BDA-
Was this the thread? There is one other too. I couldn't find it though    http://www.lotuseuropa.org/LotusForum/index.php?topic=1283.msg11145#msg11145 (http://www.lotuseuropa.org/LotusForum/index.php?topic=1283.msg11145#msg11145)
Title: Re: New rear hub design .
Post by: BDA on Wednesday,May 22, 2019, 11:06:31 AM
I think that's the one I was thinking about, Andy. Thanks for finding it!

While we're on the subject of rear uprights, we also had a thread where some of us considered alternatives to casting (http://www.lotuseuropa.org/LotusForum/index.php?topic=379.msg23665#msg23665).

edit: included a link to another thread and then fixed it!
Title: Re: New rear hub design .
Post by: dakazman on Wednesday,May 22, 2019, 11:18:56 AM
Lol BDA,
Check your link!
Good story though.
Dakazman
Title: Re: New rear hub design .
Post by: BDA on Wednesday,May 22, 2019, 11:27:01 AM
Oops!!!  :o  I've fixed it now.
Title: Re: New rear hub design .
Post by: LotusJoe on Wednesday,May 22, 2019, 11:37:21 AM
Found a few more pictures

(http://www.lotuseuropa.org/gallery/albums/Zetec/TCSpecial_uprights_3.jpeg)

(http://www.lotuseuropa.org/gallery/albums/Zetec/TCSpecial_uprightd_2.jpeg)

(http://www.lotuseuropa.org/gallery/albums/Zetec/TCSpecial_uprights_1.jpg)

Title: Re: New rear hub design .
Post by: dakazman on Wednesday,May 22, 2019, 11:47:18 AM
Nice Joe , good find.

I sent out an instant message to topyard61 as to price and availability, however still no answer.
Dakazman
Title: Re: New rear hub design .
Post by: BobW on Wednesday,May 22, 2019, 02:26:03 PM
I've wondered the weight difference between original period wheels, tires (tubes?) compared to new aluminum wheels, tires. Is there much of a difference? Is there a comparison out there somewhere?
Europa steel wheel (no trim ring or hubcap) - 11.8 lb or so
Steel wheel as above with Dunlop SP4N 145SR13 - 24.8 lb (more accurate)

I'm unable to remember why this tire is not a 155x13 but I doubt the weight difference would be appreciable.
Title: Re: New rear hub design .
Post by: jbcollier on Wednesday,May 22, 2019, 05:43:12 PM
Again, can't really see the need for a new upright.  New rear spindle?  Another matter entirely.  I'm in the middle of fitting a variation on this style of rear spindle:

https://kelvedonlotus.co.uk/product/race-drive-shaft-kit/

Mine is this one:

https://jbcollier.smugmug.com/Lotus-Europa/i-cQpwGW8/A

Now this is a proper spacer:

https://jbcollier.smugmug.com/Lotus-Europa/i-BCMxN3J/A

Will be doing a full report soon.  All I can say right now is that it's a really, really good way to go.
Title: Re: New rear hub design .
Post by: BDA on Wednesday,May 22, 2019, 08:09:59 PM
I agree, JB. Unless you need one, there's nothing wrong with the design of the stock uprights and if yours are damaged, I think they can be repaired with less expense than buying new after-market uprights. Better stub axles are a better investment.

Did you get yours from Kelvedon Lotus or someplace else? Did you shop around? If so, would you care to let us know what prices you found?

From what I know (and I haven't really researched it) suppliers of alternate stub axles are: Banks, Kelvdeon Lotus, and dogrings.com (but I don't know if he's currently selling them). Are there others?
Title: Re: New rear hub design .
Post by: lotusfanatic on Thursday,May 23, 2019, 03:29:18 AM
They look superb!   :trophy:


Found a few more pictures

(http://www.lotuseuropa.org/gallery/albums/Zetec/TCSpecial_uprights_3.jpeg)

(http://www.lotuseuropa.org/gallery/albums/Zetec/TCSpecial_uprightd_2.jpeg)

(http://www.lotuseuropa.org/gallery/albums/Zetec/TCSpecial_uprights_1.jpg)
Title: Re: New rear hub design .
Post by: jbcollier on Thursday,May 23, 2019, 05:27:26 AM
Mine are from dog rings but there are issues.  They are a direct replacement for the stock Imp axle.  However, the Europa uses a different brake set up so Lotus added a spacer to move the flange out further.  On a long spline set up, such as the Imp axle, this is not much of an issue.  But, with the short spline of the redesign, it is.  So I'm in the middle of installing the axles without any outboard spacer and then shimming out the brake drum.

Also unfortunately, the dog ring yokes were not machined properly.  I didn't discover this until much later as I bought them in 2014 and didn't check until last year.  The dog ring chap is pretty old and was very confused at the time I bought the set so I decided to sort it locally.  Cutting splines on a properly set up jig is a doodle.  Cutting splines from scratch with no dimensions quite a bit less so.  I had to take it to a big industrial shop and it cost the earth to sort.

So, for all those reasons, I would go with the Kelvedon axles as they are designed as direct Europa replacements so no need to mess with custom shims, nor worry about spline engagement.
Title: Re: New rear hub design .
Post by: jbcollier on Thursday,May 23, 2019, 05:30:20 AM
All that said, the dog-ring axles attach the yokes in a much cleverer way than the Kelvedon axles.
Title: Re: New rear hub design .
Post by: dakazman on Thursday,May 23, 2019, 08:28:02 AM
Hi,

Sorry for the late contact!

I received a reply today and I passed it on completely below.
I also conveyed an invitation to our site and interests.

In the case of lotus europa sp rear upright,
 The production is requested to a company that produces Honda's formula one vehicle, prototypes of HRC such as Motogp, etc.
 The data of lotus europa sp genuine upright is generated by a three-dimensional measuring device, and after data correction, the material is A5052 and is cut by a 5-axis processing machine and finally finished by hard alumite.  .

 It is a price, but it will be 500000 yen (excluding tax) with the left and right set in Japanese yen.

Regards,
GARAGE TOPYARD,
Title: Re: New rear hub design .
Post by: RoddyMac on Thursday,May 23, 2019, 08:32:28 AM
Wow!  That's a little on the spendy side of things, roughly $4550.00 USD for a pair. 

And, I'm surprised they are using 5052.  I would have thought 6061 would be the preferred alloy as it's heat treatable. 
Title: Re: New rear hub design .
Post by: BDA on Thursday,May 23, 2019, 08:33:35 AM
JB - Thanks. I look forward to your write up!

D'man - at $4500+, I think I'll pass. They are pretty, though.
Title: Re: New rear hub design .
Post by: dakazman on Thursday,May 23, 2019, 08:49:48 AM
 :FUNNY:e
I didn’t do the conversion. OMG 😮
I haven’t got that much in total on mine yet.
Dakazman
Title: Re: New rear hub design .
Post by: BDA on Thursday,May 23, 2019, 08:56:53 AM
I think that's a pretty good indication of just how Europa-crazy the Japanese are!
Title: Re: New rear hub design .
Post by: LotusJoe on Thursday,May 23, 2019, 09:20:38 AM
Hi,

Sorry for the late contact!

I received a reply today and I passed it on completely below.
I also conveyed an invitation to our site and interests.

In the case of lotus europa sp rear upright,
 The production is requested to a company that produces Honda's formula one vehicle, prototypes of HRC such as Motogp, etc.
 The data of lotus europa sp genuine upright is generated by a three-dimensional measuring device, and after data correction, the material is A5052 and is cut by a 5-axis processing machine and finally finished by hard alumite.  .

 It is a price, but it will be 500000 yen (excluding tax) with the left and right set in Japanese yen.

Regards,
GARAGE TOPYARD,

That's $4,562.02 just in case anyone was curious !!
Title: Re: New rear hub design .
Post by: Certified Lotus on Thursday,May 23, 2019, 09:53:11 AM
Just as I thought, made on a C&C machine. The first one is always expensive due to engineering input into the computer (although a laser would copy an original fairly quickly). After that they can knock these out fairly quickly with only machine time and then threading for the bolts. Couple of sacrificial prototypes to adjust the details and then full production.
Title: Re: New rear hub design .
Post by: jbcollier on Thursday,May 23, 2019, 10:09:44 AM
Kelvedon sells them as well at £645 per side.  Not cheap!  But much cheaper than the Japanese ones.  Kelvedon also sells new cash radius arms with a removeable side plate so you can remove the upright complete without having to pull the spindle.
Title: Re: New rear hub design .
Post by: dakazman on Thursday,May 23, 2019, 04:56:26 PM
JB, I can’t wait for your upright mod . The spacer your picture shows a beast compared to what’s installed in an s1 and s2 . Dave bean parts book has a good guide on rebuilding them. I will need to measure them for the 2 1/8 nominal call for .
 What part did you sleeve on your upright? Are you using the same inner and outer bearings, seal and slinger?
Dakazman
Title: Re: New rear hub design .
Post by: jbcollier on Friday,May 24, 2019, 06:29:51 AM
The bearing bores on the upright were oversized and steel sleeves pressed in.  With the change in yokes, no seal or slinger.
Title: Re: New rear hub design .
Post by: dakazman on Friday,May 24, 2019, 07:02:35 PM
Now I see it.
Will it work with drum brakes or just rear disc brakes?  I have some time before I start going down a modified system but I’ll keep waiting.
Dakazman
Title: Re: New rear hub design .
Post by: jbcollier on Friday,May 24, 2019, 09:29:31 PM
It will work with the stock drum brakes, or any disc kit meant for the Europa.