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Forum; 19" wheels topic

I managed to delete all of Duncan's postngs. If/when we get a back-up restored it will be a bit out of date. Some concern was expressed at losing this topic so I copied from the forum ansd preserved it here.

f3mickey



Joined: 12 Feb 2011
Posts: 7
          
dear all.. the supersports has been ordered and now I'm going through the pregnancy and planning phase. can anyone tell me if they have experience with using 19" wire wheels ( as on an MG TC ). My donor gearbox is from a Mehari and has low gear ratios which I gather would result in more torque but lower speeds with standard wheels. I was planning on using the MGA 15" wheels that Phil suggested I purchase locally to save shipping costs but wonder if the larger diameter wheels would give better speeds ( especially in 1st and 2nd gears ) and perhaps a more vintage look. but primarily I am concerned about any undesirable results with steering geometry or posture that might occur with the use of the larger wheels. looking forward to your comments and expertise.
cheers, f3mickey in phoenix
colin wilson



Joined: 20 Apr 2006
Posts: 186
          
Hello Mickey
I used the 15" wheels and after regreted it. I think motorcycle style wheels are the way to go, significant weight saving this outweighs the bigger footprint of the MG wheels by a long chalk. Pembletons handle superbly and with the 19" option and power availble you won,t overcome the tyres capability.
Good Hunting
david



Joined: 04 Feb 2006
Posts: 539
Location: France
          
There are also outer laced TA wheels that set the rim more inboard which could help with King pin inclination and avoid wheel wobble.
The TC rims are centre laced -done at the time to allow a slightly wider body on the TC for the american market. They are heavy with adaptors and spinners etc.. Alloy bike rims and hubs weigh far less...but more difficult to source .. maybe look at Triking who use 18" acront rims and in house hubs machined from aircraft billet alluminium. That may get better rolling radius.
Avon 400 tyres will really grip and give you a good feel of road surface. I found they were as good as 145x15s for grip.but look so much better.
claus



Joined: 19 Jun 2006
Posts: 93
Location: Bavaria, Southern Germany
          
Hallo Mickey,
changing to 19" wheels will give you a "longer" gear rating of about 10%, (calculated with 95/80-19 tires), nearly the same as 155/80-15.
http://www.jennyxxx.de/reifenrechner_blau.swf
I used these tires on a Lomax-type-threeweehler some month hand found the roadholding with these crossply-tires terrible, but the vintage look is great. On my supersport I use 165/80-16 radial tires (the smallest available, gear rating + 12%)
Regards
Claus _
________________
30 wheels, 20 cylinders, 577 hp, but on 8 cars
Mercedes, CX, 2CV, Burton, Lomax223, Supersport, Marcos V8
bumbly1



Joined: 09 Oct 2009
Posts: 375
Location: Edinburgh Scotland
          
Good to hear your kit is on order
I agree fully, the 15" wire wheels are heavy as are the tyres and adapters, they also require wider and heavier mudguards. The overall unsprung weight must be much more than the original Citroen design but I have not weighed them. Narrower, lighter and taller wheels and tyres is the way to go though, personally, I would also prefer to upgrade the rear wheel too so that the spare will fit all, I have not looked into how easy/difficult that would be. Reduced unsprung weight will improve roadholding and handling.
However, I understand it is not a simple process. During my build I looked at Ford model A type wheels which are also three stud (but at different centres and would need filling and re-drilling) it is unlikely old wheels like them would stand up to the use and abuse from modern driving. MG TC wheels may be an option however they are heavy too and will require heavy adapters.
Silverfish was talking about developing lighter larger diameter wheels at one point using motorcycle rims which are very light and a machined hub but I don't know what has come of this but he has proved it is possible, I think his look superb.
I don't know about the ratios issue but I would imagine there are a few Citroen options which should fit the box?
Have fun.
Tom
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Grasshopper Supersport SWB #181
MartinClan



Joined: 30 Aug 2010
Posts: 60
Location: Bedfordshire          
          
It would be interesting if someone has the actual weights of the wheel options. A lot has been said about how heavy wire wheels are compared to the original 2CV steelies - but how much heavier and is much of that down to the adapter? (which could be refined I guess...)
Robin
bumbly1



Joined: 09 Oct 2009
Posts: 375
Location: Edinburgh Scotland
          
MartinClan wrote:
It would be interesting if someone has the actual weights of the wheel options. A lot has been said about how heavy wire wheels are compared to the original 2CV steelies - but how much heavier and is much of that down to the adapter? (which could be refined I guess...)
Robin
Martin, good idea! 2CV steel wheel with Michelin X tyre 10.2 kgs, 60 spoke 4.5 j wire wheel with 165 x 15 radial 18.2 kgs, knock on .6 kgs, I don't want to remove the adapters but perhaps someone has one around but I reckon it will come to 20kgs at least making a difference of 10kgs unsprung weight, per wheel. Though not twice the unsprung weight when the other components are considered but a substantial increase on the design weight when, as in my case, a mudguard and support are added and even though I have pared down my aluminium mudguard to the minimum that still adds up to another 1kg. I am no mathematician but I think of it as an additional 11kg sledge hammer flying up and down on each bump which must mean less road contact!
Tom
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Grasshopper Supersport SWB #181
MartinClan



Joined: 30 Aug 2010
Posts: 60
Location: Bedfordshire 
          
bumbly1 wrote:
60 spoke 4.5 j wire wheel with 165 x 15 radial 18.2 kgs, knock on .6 kgs
Gosh - or words to that effect. I thought that when wire wheels were originally introduced the idea was to reduce the unsprung weight. I wonder how much of that is due to the wider tyres though...
Robin
bobgilpatrick



Joined: 01 Jun 2007
Posts: 176
Location: South Daytona, Florida, USA
          
This wheel discussion would not be a good one to lose (among others) when correcting the error of the webmaster by downloading a backup version of the Forum.
Bob Gilpatrick
David Tocher



Joined: 06 Feb 2006
Posts: 324
Location: Limerick (Ireland) and Leeds
          
I've saved this topic and it will appear in ePAG - if people want any other topics saving then let me know and I'll do my best to keep 'em for posterity!
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David - #189 LWB Super Sport 'Quicksilver'
Sambike



Joined: 16 Feb 2009
Posts: 58
Location: Stockton on Tees
          
There's a letter on relative wheel weights in PAG 17. The unsprung weight argument is significant---that plus the cost and maintenance/cleaning of wires made me go for steel wheels.
f3mickey



Joined: 12 Feb 2011
Posts: 7
          
dear all,
I've sourced MGTA 19" outer laced wheels 10kg ( the ceter splines of which should match the adapters that Phil will supply (for the MGA wheels that Phil would have supplied ) and I intend to mount excelsior or blockley 400/450-19 triple stud tyres that weigh 18 lbs . Their correct vintage appearance and great performance characteristics I am guessing will suit the supersports. do you believe the unsprung weight will be an issue? will the larger diameters create greater stability? gyroscopic effect?
I hope the lower gearing of my Mehari gearbox will handle the larger diameter tyres without too much strain and give a smoother and more efficient speed distribution through the gears. the tread face of the triple studs is more automotive (flat) than motorbike (rounded) .. will that be undesireable?
I had toyed with the idea of sourcing motorcycle wheels and tyres but I imagine they would have to be custom laced using MG A or T series center hubs or some such in order to fit the splines of the supersports ????
your input will be greatly appreciated.
cheers, mickey in phoenix
colin wilson



Joined: 20 Apr 2006
Posts: 186     
          
A word of caution on the Blokley tyres on my non Pembleton project I used Blokley's on the front axle and Excelsior's on the rear, same tread pattern and size the Blokley's were not acceptble at IVA due to not having the reqiured details stamped on them - a 300 pound error plus runnning about to resolve it.
bumbly1



Joined: 09 Oct 2009
Posts: 375
Location: Edinburgh Scotland
          
f3mickey wrote:
........ do you believe the unsprung weight will be an issue?
Mickey, if the bare wheel is 10Kgs, the same as a 2CV wheel with tyre and tube, the tyre is 8kgs, tube say .5kgs, adapter say 1kg (guess) and then the mudguards and supports (as I think you are planning turning ones) which will be at least another 1kg then you will be quite a way over what I guess to be the design parameters for unsprung weight, about 10.5kgs over. Surely any increase in the unsprung weight is going to have an adverse effect on ride and handling and 10.5kgs is quite a bit of weight? I have a wire wheel on the back too and the effect of the extra weight is more noticable there, the large diameter wheel users seem to restrict use to the front wheels, this may be because a larger wheel will not fit at the rear, I dont know. BTW I hope I don't sound like a smart *ss, I am just looking for a solution too! .
Tom
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Grasshopper Supersport SWB #181
bobgilpatrick



Joined: 01 Jun 2007
Posts: 176
Location: South Daytona, Florida, USA
          
Tom has uncovered a problem I imagine all LWB Supersports builders have run into when trying to fit a larger tire at the rear. The distance from the outside of the tire to the spare wheel carrier chassis members decreases as the body comes down due to the weight of the car, people, spare tire and baggage pushing the rear arm up into the chassis. My 155R15 tires just make it at a deep up movement of the arm and with the mudguard I installed over the rear tire actually scrapes. That's why I am going to install the ECAS updated springs to better be able to restrict the upward movement of the rear tire with two people on board. The bump stop does not alleviate the problem when using the large tires. It seems to me a 19" tire at the rear may experience this problem. I can't see extending the chassis to accommodate a larger tire as a solution as the LWB SS is long enough.
mbowden



Joined: 02 Jul 2007
Posts: 13
Location: Bristol (Portishead)
          
Hi Gents,
I have today taken some measurements using that wonderful, universal, highly accurate instrument, the Bathroom Scales, with the following results.
Wheel Phils supplied Wire Wheel plus Toyo 155Rx15 tyre plus tube, 14.0 Kg
Adaptor 2.5 Kg
Wheel Nut 0.5 Kg
Combined total 17.5 Kg
I appreciate that the number don't add up but the scales only have crude graduations.
I hope this info is of some use.
Mike.
duncan grimmond



Joined: 09 Mar 2011
Posts: 15
Location: N.Yorks
          
That would seem to indicate that the unsprung weight increases by 4 * 7.3kg/15.8 lbs. That's over a stone (or 5 * 3lb bags of flour) per wheel which seems a lot to me.
I must go and weigh a standard Citroen wheel with a Toyo tyre.
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Duncan Grimmond
BMW Brooklands "Silver Surfer"
bumbly1



Joined: 09 Oct 2009
Posts: 375
Location: Edinburgh Scotland
          
mbowden wrote:
Hi Gents, I have today taken some measurements using that wonderful, universal, highly accurate instrument, the Bathroom Scales, with the following results.
Wheel Phils supplied Wire Wheel plus Toyo 155Rx15 tyre plus tube, 14.0 Kg
Adaptor 2.5 Kg
Wheel Nut 0.5 Kg
Combined total 17.5 Kg
I appreciate that the number don't add up but the scales only have crude graduations. I hope this info is of some use.
Mike.
Mike, I used a digital hand scale but I don't really know how accurate it is but I understand my wheels are the same as those supplied by Phil, my tyres are 165 x 15 Uniroyal Rallye T's which will be heavier and there is a tube fitted, I have re weighed them taking more care this time and my combined wheel, tyre and tube is 16.8kgs not 18.2kg as I posted earlier but still quite a bit heavier than yours. The adapter, which I had not weighed is quite heavy too.
Tom
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Grasshopper Supersport SWB #181
duncan grimmond



Joined: 09 Mar 2011
Posts: 15
Location: N.Yorks 
          
Citroen wheel with Toyo tyre weighs 11.9k. so a wire wheel seems to be approx. 5.5kg heavier or 4 bags of flour per wheel. A lot of weight slapping up and down on the bouncy bits, ooerr missus........ _________________

Duncan Grimmond
BMW Brooklands "Silver Surfer"
bumbly1



Joined: 09 Oct 2009
Posts: 375
Location: Edinburgh Scotland
          
duncan grimmond wrote:
Citroen wheel with Toyo tyre weighs 11.9k. so a wire wheel seems to be approx. 5.5kg heavier or 4 bags of flour per wheel. A lot of weight slapping up and down on the bouncy bits, ooerr missus........
Duncan, is that your slightly wider tyres? My 2cv wheel came to 10kgs with worn Michelin tyre and tube. Then add the adapter which is required at 2.5kgs and the retaining spinner or knock on at say .5kgs and I make that 8.5kgs per wheel even with my shonky maths not to mention the mudguards and supports.
Tom
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Grasshopper Supersport SWB #181
duncan grimmond



Joined: 09 Mar 2011
Posts: 15
Location: N.Yorks
          
Tom, I've gone for the larger 155*15 Toyos. I think they are a great improvement. I'll go and weigh a steel wheel with a Firestone next.
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Duncan Grimmond
BMW Brooklands "Silver Surfer"
duncan grimmond



Joined: 09 Mar 2011
Posts: 15
Location: N.Yorks
          
Citroen wheel with Firestone 135*15 weighs 10.2kg so the increase in weight with the Toyo is only 1.7kg. Just over a 3lb bag of flour. Ah, the cost of bling!
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Duncan Grimmond
BMW Brooklands "Silver Surfer"
ken



Joined: 16 Dec 2010
Posts: 29
Location: UK
          
Duncan,
I never realised that 1lb of flour had been adopted as a standard unit of weight in Yorkshire.
Mind you, I guess that it's quite close to 1lb of coal...
ken
duncan grimmond



Joined: 09 Mar 2011
Posts: 15
Location: N.Yorks
          
As I do a bit of baking it's a handy item for comparison. I understand the the Home Rule for Yorkshire party wanted a weight system based on the York Ham but as a vegetarian I have to improvise.
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Duncan Grimmond
BMW Brooklands "Silver Surfer"
Rob A



Joined: 15 Jan 2008
Posts: 113
          
Hiya Duncan.
I always was told that a Yorkshire Ham was a very poor actor in Weatherby!
Best wishes to you all.
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Rob A.
f3mickey



Joined: 12 Feb 2011
Posts: 7
          
yorkshire ham indeed. now you've got me a bit concerned about the unsprung weight.. but I do want the look. perhaps I could inflate the tyres with helium ? ;>)
david



Joined: 04 Feb 2006
Posts: 539
Location: France
          
When I originally weighed wheels etc-as someone mentioned it was in PAG 11 weights were for original 2cv wheel and 125 michelin also minilite alloys with 3 hole fixings with 135 tyre and spokey wheel with 135 and 145 tyres -bigger tyres bigger weight.
There is a big difference to unsprung weight.
I never had any problem with rear wire wheel and 135 tyre rubbing...I had also fitted an old lomax front wing up under there to prevent-or at least slow down water spraying out of the rear...
David.
duncan grimmond



Joined: 09 Mar 2011
Posts: 15
Location: N.Yorks
          
Perhaps the lack of "concerned" posts on the subject of unsprung weight indicates that there haven't been too many problems. Has anyone reported undue wear to king-pins or steering joints? The shockers may be working overtime but gas ones would deal with that.
There are quite a lot of the spoke-wheel/adaptor versions out there so if you have them and they aren't causing noticeable adverse effects I would guess that you'll be OK.
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Duncan Grimmond
BMW Brooklands "Silver Surfer"
bumbly1



Joined: 09 Oct 2009
Posts: 376
Location: Edinburgh Scotland
          
duncan grimmond wrote:
Perhaps the lack of "concerned" posts on the subject of unsprung weight indicates that there haven't been too many problems. Has anyone reported undue wear to king-pins or steering joints? The shockers may be working overtime but gas ones would deal with that. There are quite a lot of the spoke-wheel/adaptor versions out there so if you have them and they aren't causing noticeable adverse effects I would guess that you'll be OK.
Duncan

I don't think it is a case of reliability problems, more a case of improving roadholding?
Tom
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Grasshopper Supersport SWB #181
duncan grimmond



Joined: 09 Mar 2011
Posts: 16
Location: N.Yorks
          
Having only driven with Citroen wheels, I think I would be hard pressed to improve the incredible road-holding of a Pembleton (Brooklands). Mine feels like it's on rails and the harder you push it the deeper it digs in.
Do you have roadholding problems? What happens when you push it in a corner?
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Duncan Grimmond
BMW Brooklands "Silver Surfer"

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