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Old 21st June 2011, 15:02   #1276
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re: The Offroad Rims & Tyres Thread

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I have re thread my old Pirelli Scorpion 215/75 R15 2 years back. It has run around 5000 kms of ONROAD and OFFROAD use. Touchwood - No complaints

Currently doing duty on a friends gypsy!!
WOW. I did not know radials (soft) can be re-threaded, somehow i was told only the harder LCV/NDMS kinda tyres can be done. Cool, where did you get it done? Chennai?
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Old 21st June 2011, 15:45   #1277
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re: The Offroad Rims & Tyres Thread

Hi Mr. Fazal,

Thanks for your post. I have bought the Onyx Wheels from Mumbai and they really are very nice. I will post some picture soon i.e., as soon as I can get the MT tyres for these wheels.

Regards

Jaskirat
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Old 21st June 2011, 22:59   #1278
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re: The Offroad Rims & Tyres Thread

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Originally Posted by Jaggu View Post
As long as the re-thread stays glued to the old carcass its fine, am not sure how much they would with offroad abuse, unlike onroad use.

Don't worry jaggu, I have done 90 percent of my offroading on re-threaded NDMS tyres with out any problems so far...

Last edited by khan_sultan : 13th July 2011 at 16:31. Reason: fixed quotes for better readability
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Old 2nd July 2011, 13:14   #1279
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re: The Offroad Rims & Tyres Thread

Hello Guys

What is the offset on the stock rims of a Gypsy? Is it positive or zero or negative?

I am contemplating changing from the stock 15x5J PCD 5x139.7 type wheels to 15x7J PCD 5x139.7 wheels. I use Yokohama Geolander AT/S 215/75/R15 currently.

I plan to add 5mm of extra clearance between inside wheel and leaf/struts. Curiously when I checked on this online offset calculator (Wheel Offset Calculator) it shows me no improvement in clearance upto a -25mm offset. And to obtain a 5mm clearance I would need -30mm offset according to that page.

Is this tool accurate?

Thanks
--Ragul
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Last edited by Ragul : 2nd July 2011 at 13:16.
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Old 2nd July 2011, 21:52   #1280
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re: The Offroad Rims & Tyres Thread

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Originally Posted by Ragul View Post

I plan to add 5mm of extra clearance between inside wheel and leaf/struts. Curiously when I checked on this online offset calculator (Wheel Offset Calculator) it shows me no improvement in clearance upto a -25mm offset. And to obtain a 5mm clearance I would need -30mm offset according to that page.

Is this tool accurate?

Thanks
--Ragul
Yes it is.
You are replacing a 5 inch rim with a 7 inch rim and gaining a total of 2 inches in width.
1inch = 25mm, so you are gaining 50mm.

With a zero offset rim you loose 25mm in clearance between the tyre and leaf/strut (50mm/2)
So you would need a -25mm offset rim just to maintain the existing clearance between tyre and leaf/strut and a -30mm offset to increase it by 5mm.
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Old 2nd July 2011, 21:57   #1281
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re: The Offroad Rims & Tyres Thread

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Originally Posted by gotzuk View Post
Yes it is.
You are replacing a 5 inch rim with a 7 inch rim and gaining a total of 2 inches in width.
1inch = 25mm, so you are gaining 50mm.

With a zero offset rim you loose 25mm in clearance between the tyre and leaf/strut (50mm/2)
So you would need a -25mm offset rim just to maintain the existing clearance between tyre and leaf/strut and a -30mm offset to increase it by 5mm.

Gotzuk

OK I was expecting the extra 2" to be extending/padding up completely on the outside only. I guess zero offset rims are centered where the bolts are concerned.

Will this -30mm offset increase stress on wheel bearings and axle?

I plan to do moderate offroading not the extreme stuff.

Thanks
--Ragul
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Old 3rd July 2011, 07:31   #1282
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re: The Offroad Rims & Tyres Thread

Friends,

Where can i get Maxxis bighorn 245/75/R16 in bangalore/coimbathur/Kerala ? I need only two.
is it a good choice for MM550 ?

- Ssreejesh
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Old 3rd July 2011, 10:21   #1283
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Quote:
Originally Posted by Ragul

Will this -30mm offset increase stress on wheel bearings and axle?

I plan to do moderate offroading not the extreme stuff.

Thanks
--Ragul
Yes there would be extra load on the kingpin bearings and steering tie rod ends but nothing to really lose sleep over.
As long as the tyres don't foul with the fenders/leafs, you are good to go.
Cheers
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Old 3rd July 2011, 11:46   #1284
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re: The Offroad Rims & Tyres Thread

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Originally Posted by sreejeshmp View Post
Friends,

Where can i get Maxxis bighorn 245/75/R16 in bangalore/coimbathur/Kerala ? I need only two.
is it a good choice for MM550 ?

- Ssreejesh
@sreejeshmp, In my search, I came across an importer in Bangalore who is stocking maxxis bighorns. Berick Impex, Contact Yash @ 9620962020. I found his price expensive. But I could not find anyone else dealing with Maxxis Bighorns in Bangalore. Let us know if you get and the price he is quoting.
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Old 12th July 2011, 17:59   #1285
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re: The Offroad Rims & Tyres Thread

Quote:
Originally Posted by gotzuk View Post
Yes it is.
You are replacing a 5 inch rim with a 7 inch rim and gaining a total of 2 inches in width.
1inch = 25mm, so you are gaining 50mm.

With a zero offset rim you loose 25mm in clearance between the tyre and leaf/strut (50mm/2)
So you would need a -25mm offset rim just to maintain the existing clearance between tyre and leaf/strut and a -30mm offset to increase it by 5mm.

Is the stock rim of the Gypsy with Zero offset? I saw somewhere that it is actually -10mm and that would mean I will require -40mm offset with new rims.

--Ragul
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Old 12th July 2011, 18:30   #1286
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re: The Offroad Rims & Tyres Thread

Was in a dilemma as to what size wheels to use for my Mm550 which will have tyres of 15"x31x10.5 Maxxis Bighorns.

The design i likes was the Mickey Thomson replica 8J ones. The other was a 8.5J and the same MT design on the 10J rims. A lot of advice later i was convinced that the !)J rims are not for the above tyres. So im gong in for any good 8J design tomorrow or then the MT 8J. Hopefully, on the 8J, the tyres will not pop out from the rim when the psi is dropped for rocky/sandy terrain, as is the fear in the 10J.
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Old 12th July 2011, 19:02   #1287
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re: The Offroad Rims & Tyres Thread

I just discovered something called backspace. A new rim with lesser backspace should allow me to use a wheel with lesser negative offset should it not?

For example if stock rim has 4" backspace from flange to the mounting pad, then a wheel with 3" backspace will have 1" extra clearance from the inside wheel to the shock strut mounts or suspension leaf. And that would mean I can reduce the offset requirement by -25mm?



--Ragul

Last edited by Ragul : 12th July 2011 at 19:11.
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Old 13th July 2011, 14:03   #1288
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re: The Offroad Rims & Tyres Thread

Quote:
Originally Posted by Ragul View Post
Is the stock rim of the Gypsy with Zero offset? I saw somewhere that it is actually -10mm and that would mean I will require -40mm offset with new rims.
Yes. And with the new 7J rims and a -40mm offset, your outer wheel line would move outwards by 55mm.



Quote:
Originally Posted by Ragul View Post
I just discovered something called backspace. A new rim with lesser backspace should allow me to use a wheel with lesser negative offset should it not?

For example if stock rim has 4" backspace from flange to the mounting pad, then a wheel with 3" backspace will have 1" extra clearance from the inside wheel to the shock strut mounts or suspension leaf. And that would mean I can reduce the offset requirement by -25mm?
Actually, wheel offset and backspace are just two different ways to measure a rim and are interdependent.
Wheel offset is the distance between the rim centerline and the rim mounting pad.
Backspace is the distance between the rim mounting pad and the inner rim line.
You can't change the offset without changing the backspace values and vice versa.

For example, the 5J (125mm) Gypsy rim has -10mm offset, which means that the rim mounting pad is 10mm from the rim centerline (62.5mm) towards the inner rim line. So the backspacing in his rim is 52.5 mm (62.5 - 10)

If you decrease the backspacing by 10mm (to get more space between the strut/leaf and rim) to 42.5mm, then the offset of the rim would automatically become -20mm.

Hope I am making sense
Cheers
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Old 13th July 2011, 23:13   #1289
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re: The Offroad Rims & Tyres Thread

Quote:
Originally Posted by gotzuk View Post
Yes. And with the new 7J rims and a -40mm offset, your outer wheel line would move outwards by 55mm.

Actually, wheel offset and backspace are just two different ways to measure a rim and are interdependent.

Hope I am making sense
Cheers

Yes I realized soon after I made that post. Thanks for clarifying that.

After scouting JC road and searching Indian websites, getting the right wheels appears to be more difficult than I thought. In fact the prospects of finding a wheel design and pattern I like and that will work without the inner side wall rubbing the leaf (with the required offset) looks bleak. :(

I hate the alloys with large gaps and holes in them that gives the wheels such a sparse bare bones look. Some examples of what I like (and only in dull finish)



Boohoo! Guess I will have to drop my plans until serendipity strikes!!

BTW can you confirm if Gypsy is 5J or 5.5J?

--Ragul

Last edited by Ragul : 13th July 2011 at 23:14.
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Old 14th July 2011, 01:17   #1290
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re: The Offroad Rims & Tyres Thread

Quote:
Originally Posted by Ragul View Post
Hello Guys

What is the offset on the stock rims of a Gypsy? Is it positive or zero or negative?

I am contemplating changing from the stock 15x5J PCD 5x139.7 type wheels to 15x7J PCD 5x139.7 wheels. I use Yokohama Geolander AT/S 215/75/R15 currently.
Quote:
Originally Posted by Ragul View Post
Is the stock rim of the Gypsy with Zero offset? I saw somewhere that it is actually -10mm and that would mean I will require -40mm offset with new rims.
Quote:
Originally Posted by gotzuk View Post
Yes. And with the new 7J rims and a -40mm offset, your outer wheel line would move outwards by 55mm.
NO, Gypsy wheel is neither zero nor negative offset, it is a positive offset wheel. I am successfully using Yoko Geo A/Ts 235/70R15 on 15X7J -13 offset wheels.

For some measurements and calculations visit post nos 554 and 560 on pages 37 and 38 respectively.
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