WheelchairDriver

i want to change the solid tyres and wheels to tubeless and the only size marking on the tyres looks like 3 x 8.i don't have a lot of height clearance getting into my van so any change needs to be around the same overall diameter possibly a bit more what options are there to do this please? i know that i will need PCD but is there anything else like offset to consider ?

PCD and ofset dont much matter as YOU will be making an adapter to fit the rim as theres no plug and play way to do anything else.

Rim width is important.

Stock tyres are 3.00 x 8 in inches and thats: 3.00 inches wide/ 3 inches sidewall and fits an 8 inch rim. So 3 + 3 + 8 = diameter. Thats 14 inches.

Same overall diameter plus a tiny bit, is 120/70 (120 is mm, 70 is percentage height of sidewall) and fits an 8 inch diameter rim.

110/80 - 8 is taller and narrower. 3.50 x 8 is taller still and narrower still. Remember that a 1 inch taller tyre is only .5 inh greater ride height.

3.00 x 8 needs 1.75 to 2.5 width rim.
110/80 - 8 needs 3 to 3.5 rim.
120/70 - 8 needs 3.5 to 4 rim.

thanks, that helps a lot, i need to find a machine shop but first source some wheels and tyres. any suggested suppliers?

What size?

I got these very cheap at about 9 pounds a wheel from shirley on this forum.

viewtopic.php?f=2&t=7455&start=600#p122818 read the first post and scroll down!

Actual wheel. Scrol down. viewtopic.php?f=2&t=7455
or download/file.php?id=7426&mode=view


120/70 - 8 and stock 3.00 - 8 tyre size compared download/file.php?id=7639&mode=view
Again on the bed download/file.php?id=7646&mode=view

How to make the spacers and adapter. Only a drill needed. The rest was ordered online from a lazer cutting service...
viewtopic.php?f=2&t=7455&start=120
and viewtopic.php?f=2&t=7455&start=150

Remember that I made these spacers/adapters in my bedroom wth a drill. After some careful measuring and ordering the blank undrilled discs lazer cut online. download/file.php?id=7688&mode=view

Another tyre make. These are hard to find but prefered. They are also 120/70 - 8 tubeless. download/file.php?id=7755&mode=view

Best to read complete thread if you can...

more to confuse me, wheels are 5 bolt not 4 so i guess that this is the what i need to find. Mudguard looks like it is coming off as well.

3 4 or 5 makes no difference as YOU will be making an adapter or hub regardless, non will just bolt on.

With 120 tyre mudgaurd will be ok.

so i can go back to hunting for wheels without concern for bolt holes.

do you think that 110/80 will fit with the mudguard/ 120/70 is a little wider which i don't think is too big a problem as i am sure the maximum width is my arm rests.

The 110/80 is about 14mm taller.

I used the 120s because they look better and because they are fatter so sink less on soft ground. And because I am 20 stone and so with wide arm tops, and a 18 or 20 inch cushion they are no wider than the chair is.

Like sad mobility pram...



Now with a bit more attitude!



And the mudguard fits, with 6mm washers under the bolts


to raise them a touch.

wheelie junkie wrote:so i can go back to hunting for wheels without concern for bolt holes

Correct. BUT, you will have to be able to make adapters or at least do a drawing with correct dimensions to have adapters made.

i found these http://www.madmunk.com/wheels-8in-split ... 1-2171.php

has anyone used this company and say what the quality is like/ Not cheap when you add tax

No use for tubeless. Ask shirley, or use a monkeybike parts supplier and get one bit alloy rims.

easier said than done finding wheels1 I found these https://www.aliexpress.com/item/3-50-8- ... 461ac08066 but can't tell if they are tubeless, i've asked but is there any way you can tell from photos?

Also what is the duty charge from China?

wheelie junkie wrote:easier said than done finding wheels1 I found these https://www.aliexpress.com/item/3-50-8- ... 461ac08066 but can't tell if they are tubeless, i've asked but is there any way you can tell from photos?

Also what is the duty charge from China?

those dont look bad and price isnt bad either - there are other on the bottom of that page also -

Those are tubeless.

thanks, confirmed that they are so now on order, wait and see how much i get hit for VAt and duty.

Quite! Thats the point.
Its highly unlikely that you wont make it home. I have pulled out nails, watched it seal itself, and never bothered to repair. Self healing. Tubes? Pop!

definitely tubeless with sealant. Just got tyres to find but once again not easy. Found some on mytyres yesterday at £50.50 today £59!

Look at it this way. Cheap tyres are shit! And flimsy. And these are tubeless so no tubes to buy.

i don't mind paying for decent rubber just can't understand how they increased so much in one day. It is difficult to know how good any of the tyres that i found are, unknown brands like strident for example. https://www.stridentbatteries.com/produ ... 70-8-tyre/

Those are made specifically for the mobility industry and are cheap weaker and not tubeless.

Burgerman wrote:Those are made specifically for the mobility industry and are cheap weaker and not tubeless.

thanks, i'll avoid.

You can also get 3.50-8 tires and wheels from Shirley which are nominally only 1/2" taller and wider than the stock 3.00-8 tires, which is only a small height increase, especially if you run the tubeless tires on the soft side (gives a nicer ride) and doesn't have the added width of the 120/70-8's that BM likes (us slightly skinnier types want to keep the width down.... )

You'll still need to make adapters...

The other potential 'gotcha' is that the tires I got from Shirley are very close to nominal size, but the stock solid 3.00-8's that were on my project chair are much smaller, I'd say closer to 2.50-8 actual, so you might end up with a bigger size increase than the nominal sizes would lead you to expect...

ex-Gooserider

Got them fitted, with 5mm clearance to motor 70cm wide, armrests are 68cm so not too big a difference. Just got to get this pressure sore healed to try them!

Thats more like it!

Why dont they come like this?

Grey front tyres?


Picture of full chair and model would be nice!

very nice - looks Cool - where did you get the Rims ?
Shirley or on your own ?

is that a 3.5inch rim ?

Burgerman wrote:Thats more like it!

Why dont they come like this?

Grey front tyres?


Picture of full chair and model would be nice!

Still got to swap the fronts, that is my night shift support workers job tonight. Black, tubed tyres to replace grey stock ones. More work to do before photos, trying to get a central footplate, don't know how much shorter it'll be as the casters touch my heels now if tilt is level.

Is 70cm a reasonable width? Really looking forward to getting outdoors in it.