Hi. I am building a 1979 Mk2 V50 special and wonder what the widest rear tyre could be had on the standard wheel rim please? I have had the rear drive powder coated so want to use that. Would another MG model's rear wheel fit the swingarm and give me a slightly wider wheel? I believe I have the option to go up a size in terms of tyre for the rear, going from 100/90/18 to a 110...would a 120 fit my standard wheel? The whole purpose of this is because I have a modern front end on the V50 and will probably need to use the corresponding wheel which has a tyre size of 120/70/17 which I could reduce to 110 I believe. I want to avoid having front and rear tyres the same width if I can. Any help greatly appreciated. Thanks
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V50 rear wheel width.
- Thread starterremfanuk
- Start date
Paul Brice
Tuned and Synch'ed
AFAIK for V50 the problem is fitting the tyre in the gap between the cush drive splines & the swing arm (& the rear mudguard but at least that's possible to loosen etc); I don't think it's the wheel itself that limits the tyre width - so changing the wheel won't solve the limitation. I run standard 100/90R18 on the back & it's already tight....you MIGHT be able to go up to 110 but that might involve letting the air out to get it in....120 probably not.
Or remove the rear drive with the wheel every time.
Someone told me that they think they fitted a 120 rear tyre to their V50 but had to let air in/out to do so. I won't be running a mudguard so that won't get in the way. For the amount of miles I will do on it, taking the wheel off with the bevel drive won't be much of a hardship. I guess what I need to be mindful of is whether a 120 rear will rub at all on the swingarm.
You may find it handles better with the stock sizes front and rear.
no doubt it would but I wouldn't be able to create the build I am undertaking. has anyone fitted a 120/90/18 rear to a V50?
What you need is back rim from a V50 or V65 Custom they took a 130/90 - 16 and fit in the swingarm. It is a 2.5" rim not 2.15"
Not many running around anymore. I just gave away an exhaust from one, sat on my shelf since late 80's.
Not many running around anymore. I just gave away an exhaust from one, sat on my shelf since late 80's.
So a V50 or V65 Custom rear wheel was wider than the non custom versions? That's interesting information Steve. But it is a 16" wheel compared to the 18" I have, or did I read that wrong? Would I need the whole swingarm, bevel box, etc. too? Should I look at V65 Florida's or is that something completely different? Do they take a different axle too? Sorry for all the questions but this might be the solution I have been looking for. Thank you
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Paul Brice
Tuned and Synch'ed
Sigh.....as I already said, the V50 wheel R18 (Mk2/3 std) WILL take a bigger tyre easy...that's not the problem & in fact if I measure the rear wheel width of my V50 Mk3 (running 100/90 R18) and my V65 Florida (running 130/90 R16) the Florida rear wheel is barely 7mm wider.....the problem is the size of the swing arm on V50 as it's small & narrow inside width.
Custom versions & bigger engine variants had wider inner width swing arms & mainly longer swing arms (with longer driveshafts & often different splines on shafts); my V65 Florida has at least 4cm more inner swing arm distance at the wheel axle cross/section (it has a much longer spacer section between the wheel cap & swing arm to compensate).
I did measure the internal swing arm end distance & looks like any swingarm will fit the V50 gearbox, but the V50C swingarm is longer (& has more room for bigger tyre); so you are likely to have to check out driveshaft length/splines to see whether you could go that way.
PS I checked & although my V50 mk3 has 12 spline driveshaft, the V50 mk2 had 10 spline driveshaft....so you could fit a V50 Mk3 box & then a V50C driveshaft & likely lengthen the rear suspension to compensate the longer back end
Custom versions & bigger engine variants had wider inner width swing arms & mainly longer swing arms (with longer driveshafts & often different splines on shafts); my V65 Florida has at least 4cm more inner swing arm distance at the wheel axle cross/section (it has a much longer spacer section between the wheel cap & swing arm to compensate).
I did measure the internal swing arm end distance & looks like any swingarm will fit the V50 gearbox, but the V50C swingarm is longer (& has more room for bigger tyre); so you are likely to have to check out driveshaft length/splines to see whether you could go that way.
PS I checked & although my V50 mk3 has 12 spline driveshaft, the V50 mk2 had 10 spline driveshaft....so you could fit a V50 Mk3 box & then a V50C driveshaft & likely lengthen the rear suspension to compensate the longer back end
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i appreciate your knowledge Paul...i don't have that where MG is concerned...i ask these questions because i wanted to clarify if Steve meant the V65c wheel would fit my swingarm as that's how i read it but was aware of what you had said previously that a 120 would probably not fit with my standard V50 swingarm. it's not unknown on forums for people to have different opinions on the same matter and state these as fact. i think GTM's suggestion of removing the rear drive if the tyre needs changing is likely the best route.
Paul Brice
Tuned and Synch'ed
Agree on that - I haven't had to change a rear tyre on my V50 since I rebuilt it in early 2020, and taking the rear drive off is a lot easier than all the changes needed for a bigger ID swing arm !