• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.
    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

Space-Saver Spare Tire....

Share this page

G

Guest

Guest
Guest
Offline
Has anyone ever used one of those space-saver spare tires off of most modern cars on a TR6? Seems to me to be a good choice to save space in the trunk as well as cut down on some weight. I, for one, am running oversized tires and one of these mounted won't fit under my gas tank. I went with a standard TR6 rim and original-sized tire. What harm could it be to use one of these skinny little tires as a come-in tire. Of course these won't work with wire wheels (5 W's in a row!) but I think they would be a smart thing to use as a spare for any other tire. I realize they are strickly for limping back but think of the cost savings.
And if this is a good option, what particular tire should one look for, or better stated, which car should they come off of. I would think the only real concern would be tire height.

Bill
 
I woulden't see any problem with matching up a "donut" spare for a TR6
I was thinking about that in the TR4, but, like you said, it has wires, and I had a spare already so I just left it.
It's not a concern with the TR2 as it has the seperate spare tire compartment that is designed to fit a full size spare.
 
[ QUOTE ]
...It's not a concern with the TR2 as it has the seperate spare tire compartment that is designed to fit a full size spare.

[/ QUOTE ]True, but it's worth noting that the earlier cars apparently had a smaller spare tire well that probably will NOT accommodate anything larger than an original 5.90 x 15 bias-ply or 155SR15 Michelin X radial.
 
[ QUOTE ]
[ QUOTE ]
...It's not a concern with the TR2 as it has the seperate spare tire compartment that is designed to fit a full size spare.

[/ QUOTE ]True, but it's worth noting that the earlier cars apparently had a smaller spare tire well that probably will NOT accommodate anything larger than an original 5.90 x 15 bias-ply or 155SR15 Michelin X radial.

[/ QUOTE ]
DOH!
I guess I'll find out soon enough.
I haven't gotten far enough to try stuffing a newer tire in there yet.
 
I use a Saab doughnut in my MGB
 
Banjo - I carry a 165/15 spare in the wheel well of the TR3A but I let all the air out, sprinkle baby powder on the sidewalls and tie a nylon strap in a loop to have something to pull. To get it out I have to lay on my back and tug with all my might (yes, I carry a 12VDC air compressor).

Bill - Some do use a space-saver spare for this application and that could work for you too. I seem to recall that a Volvo skinny-spare is an appropriate size & bolt pattern.
 
[ QUOTE ]
Banjo - I carry a 165/15 spare in the wheel well of the TR3A but I let all the air out, sprinkle baby powder on the sidewalls and tie a nylon strap in a loop to have something to pull. To get it out I have to lay on my back and tug with all my might (yes, I carry a 12VDC air compressor).



[/ QUOTE ]
I wonder if a AAA card would fit in there better.
Then I could just slide the dryrotted old Michilin X in there easily next to it /ubbthreads/images/graemlins/jester.gif
Back on topic, Yes Saab wheels are the same bolt pattern. A donut from one of those would work
 
Hi Banjo,

You could also make up your own "space saver". Get a TR2/3 4" steel wheel, or a TR4 4.5", and mount up a smaller, but standard tire. I'd suggest checking the tire's diameter, primarily, to see that it's close to the same as the rest of the tires on the car... for the safest limp-home.
 
Hello all,

I have never had one of these strange devices so I cannot speak from experience, but I wonder how the car manufacturers ever got these accepted by the authorities. Surely the vehicle dynamics are seriously compromised if a sudden evasive manouvre is required even at slow speed (What is slow, 40 mph?). An under inflated tyre of the right size makes a huge difference to the handling so how such a narrow section tyre reacts I can't begin to guess.
It is, in the UK anyway, illegal to have different sized tyres on the same axle so using a smaller tyre on a smaller wheel as suggested is not to be recommended.

Alec
 
Actually, those space saver donuts work pretty well. I've had to use them on two occasions with my Miata, and once on the wife's Mazda 6. You won't be able to do an autocross with one on, but at 65 mph on the highway it felt OK. They say to limit them to 50 mph, but one of the big car mags did some testing of the donuts and found the they were quite capable of dealing with modern traffic. Of course, this is all predicated on the fact that they are pumped up to their correct operating pressure which is usually about 60 psi.

The trend in newer cars is to eliminate the spare altogether. The manufacturers are now giving us a can of fix-a-flat. Some are including a small compressor to be plugged into the cig lighter. /ubbthreads/images/graemlins/hammer.gif
 
"I use a Saab doughnut in my MGB "
Tony, Have you used the Saab tire and wheel? Any clearance problems? The reason I ask is that the Saab is FWD. The offset on FWD wheels is different than RWD wheels.
There are plenty of choices for a 4 bolt 4.5" space saver spare. Honda Civic, Miata, Ford Tempo, Various Toyotas... However there are a couple of things to check. Many modern cars use hub centric wheels. The hole in the center of the wheel is sized for a fairly precise fit over the center of the axle hub. The design goal is to position the wheel and tire concentric to the hub/axle. The diameter of the bore in the center of the wheel varies. Many modern aftermarket wheels have an over sized bore and require a hub adapter to match the bore to the hub.
Someone mentioned hub centricity on TR6's a few weeks ago. I'm not sure this concept was in use when TR6's were in production. Them may be lug centric
My 1993 GMC Jimmy did not have hub centric wheels. I installed a set of wheels from a 2000 S10 Xtreme. The Xtreme wheels are hub centric. Unfortunately the bore on the X wheels is smaller than the boss on the hub. I had to open up the bore to fit the wheels.
The second area to check is overall clearance. FWD cars generaly have positive offset wheels. These may not clear suspension and brake components.
Tire Rack has some good tech articles covering this.
On my son's Civic we went from the stock 13" wheels to a 15" wheel. 195/50/15 tires were the best match in OD to the OEM tires. This quite a bit smaller than the standard TR6 tire, but may work for a come-in tire.
One final item to check is the compatibility of your lug nuts to the spare wheel. Alloy wheels frequently use a different style of seat on their nuts. I recently bought a set of KN wheels for the TR6. The lug nuts are very different than those on a stock wheel. Be sure to carry a set of the correct nuts.
Geo Hahn, I think Volvos are all 5 lug
martx, IMHO you should stick to the 50 mph limit. Better safe than sorry, particularly with our beloved toys.
 
I have AAA plus (first hundred miles are free) and a cell phone. I am obsessive about my tire pressure and tire conditions and have yet to be stranded by a flat tire. Especially with modern radials. I dodge potholes and watch for road hazards. Though I still could be caught out sometime I have decided to take my chances. Besides, where I like to play if I have a tire failure at speed I'll need more than a spare tire. /ubbthreads/images/graemlins/driving.gif

The spare tire well is now where I keep a can of fix-a-flat, the scissor jack, some tools, roadside emergency kit (flares, first aid etc...), blanket etc... Most of which has come in handy helping MG's that get stranded. /ubbthreads/images/graemlins/grouphug.gif

Total weight in there is still less than the spare tire and it frees up the boot for actual luggage and the tonneau. Of course in a pinch, I also have a luggage rack with some nifty leather straps to haul stuff on.

As far as the space savers, if anything additional happens while you have one on the car and you exceeded the maximum speed and distance (most have 50 mile limits), you will be SOL as far as insurance or warranty claims.

/ubbthreads/images/graemlins/cheers.gif
 
Sure beats walking. I just felt that the weight savings and extra storage would be a bonus. Has anyone come up with a specific answer as to which vehicle would be the best choice for a donor donut?

Bill
 
The SAAB doughnut wheel is different than the regular Saab wheels...I've not had to use it on the road but have put it under car & driven arouund block - no problems & it appears the rolling diameter is the same as my MGB wheels.
 
Re: Space-Saver Spare Tire....[bolt patterns]

Hi!On your MGB you used a Saab Space saver wheel & tire?
What is the bolt pattern on that? i thought tr's were 3 3/4"
And what year Saab was it.I'd like to use one of those in my Spit....Ken /ubbthreads/images/graemlins/cheers.gif
 
Unless the diameter is very close to matching, I would be very wary using a these on the back wheels. Any difference in diameter will cause LOTS of wear on the differential. This is the reason that these mini donuts are restricted for speed / mileage.
Different diameter tires will cause the diff to compensate continuously. Remember that turning causes the pinion gears to spin. Normally in a straight line, they basically don't move- no wear. Now with different size tires, they are going to more much harder than they were designed for. End result- heavy wear on the thrust bearings.
Of course on the front, this is not a concern (except on FWD cars)
Yisrael
 
Re: Space-Saver Spare Tire....[bolt patterns]

[ QUOTE ]
Hi!On your MGB you used a Saab Space saver wheel & tire?
What is the bolt pattern on that? i thought tr's were 3 3/4"
And what year Saab was it.I'd like to use one of those in my Spit....Ken

[/ QUOTE ]

TR7/8's are the only TR's with a 3 3/4" bolt pattern. TR2-6 are 4 1/2"

/ubbthreads/images/graemlins/cheers.gif
 
Re: Space-Saver Spare Tire....[bolt patterns]

Has anyone had good luck with that spare tire in a can stuff?

Bruce
 
Re: Space-Saver Spare Tire....[bolt patterns]

Actually... no. I have yet to use the stuff. Though I have had to operate a tire machine changing a tire off a wheel that had this stuff in it. Goo is a good descriptor. If you let the tire techs know its in there they will be less mad at you. /ubbthreads/images/graemlins/mad.gif

I have yet (touch wood) to be stranded by a flat tire with modern radials. The two times that I have had to have my TR6 towed (in 16 years) a spare would only have helped if I could have turned it into a unicycle.

Bill, so far it seems to not look good for answering your question. Lets put our thinking caps on people. /ubbthreads/images/graemlins/grouphug.gif

/ubbthreads/images/graemlins/cheers.gif
 
Re: Space-Saver Spare Tire....[bolt patterns]

You don't completely know your Tr's;>>GT6 & Spitfire RDST also have 3 3/4" bolt pattern.And i heard that Ford Escort Merc Mercur.Space saver will fit.A couple good salvage yards said these have 33/4 bp....And there stainless trim rings snap right on. /ubbthreads/images/graemlins/iagree.gif /ubbthreads/images/graemlins/driving.gif
 
Back
Top