636, 646 Wheel Hub Adapter

[expresso]

Ok Shirley - i decided to start a new trend here so not to change subject over at the other one -

thanks for helping to get me a hub for my chair - maybe if all works well - i can use those rims you get there also -

first i want to understand something - my chair is about 26.5 inches wide now - i dont want to make it wider - i am using the stock rims with 3.50 x 8 tires as you mentioned you used before with tubes .

i cant complain so far - chair runs good - looks good - i got rid of the front wheel wobble - 90% of the times - i get a little here and there - but nothing to worry about - so overall - its not bad -

if you made me the hub and got me those rims - i like to keep it the same width overall - 26.5 inches wide - can that work with the new rims and hub ? would i need a different size tire with OD of the stock size and same width of what i have now - if thats possible


first off here is a picture of the chair - and links to the parts list which shows the hub part number to be the same on both chairs - i have the newer motors - its 3 years old - I dont have the older larger motors - but when i look it up - it does show the same hub part number for both older and newer motors
so i would say the 636 you can use there would be the same as i have -

take a look -

thanks again - i know we talked about in the past - and you were busy getting BM and Steve rims tires etc, , if this can be done and it would be a simple wheel change for me here - maybe i can manage that then - as long as all i have to do is just get the tire mounted to the rims and then just swap tires rims off the chair -

[expresso]

here is the link to the parts for the hub - looks like number 5

https://www.quickie-wheelchairs.com/rep ... -s636-s646

theres no rush - when ever you can -

[Burgerman]

The limiting factor is the motor can in most cases. It means a tyre cannot go inwards as it will hit the motor. So take a look at that gap, and any other thing that the tyre will hit if moved inwards at all.

You need a 2 or 3mm gap minimum.
Provided you have this now, then the thing that determines the total width is the tyre width.

If you had a 3.50x8 tyre (3.5 inches) and fitted a 4.5 inch wide tyre, then each side will be 1 inch wider. Adding 2 inches to your chair.
My 120 tyres are in mm. Thats about 4 and a three quarters wide in inches. Those would be a slightly SMALLER diameter, but not much. And 1.25 inches wider each side. So your chair will be 2.5 inches wider than it is now.

With 110/80 tyre it will be .87 inches wider each side. So add 1.75 inches to your existing width.

[expresso]

As it the tire rim sits right now on my chair - its as close as it can be to the motors - i mean its so close that i didnt think it would work but it does - the tires can not go in closer the motor any more.

If i understand you correctly BM - does this mean that if i used the rims from shirley with a hub adapter he may make for me - and use the same 3.50 x 8 tire on a 2.5 rim - this would make my chair even wider than it is right now at 26.5 inches ?

i dont mind if i have to use a different tire size - i just cant find any here that make it the same OD as a stock tire rim combo and same width of a 3.50 x 8 tire that i am using now -

since my tires have that small pinched look because of the smaller rim width - its not too bad really on my chair the look - but if the rim was just a bit wider - wouldnt it just make the tire sit flusher and more even without adding width to the overall chair ?

Someone here just did tires on his chair and extended his original two part rims - it came out very nice looking actually - i am not able to do that myself but the idea is to just make it fit better with the tire - and keep same width if its possible

take a look at these - big difference over a stock tire -

[expresso]

this is another user who just did his tires - using the same tires i have size etc,

but they sit flush on his rim because he added to the rim making it a wider rim - thats a great idea he did and worked perfect - i would think he needed longer screws now and maybe the bolts to hold the rim on the motor hub ? or maybe they were just enough - either way it came out nicely done -

[Burgerman]

If i understand you correctly BM - does this mean that if i used the rims from shirley with a hub adapter he may make for me - and use the same 3.50 x 8 tire on a 2.5 rim - this would make my chair even wider than it is right now at 26.5 inches ?

No in both posts! I never mentioned rim widths. Only tyres. But a 3.50 tyre is already taller by too much. And fitting it on a wider rim means it will end up 2 to 3mm wider each side of the tyre. Knowing that, you just make the wheel adapter to move the wheel outboard by a couple of mm. So your chair will be only 1/4 inch wider overall. And the rims wont look good (too narrow, need to be on backwards, etc. All in all its a bad plan!

i dont mind if i have to use a different tire size - i just cant find any here that make it the same OD as a stock tire rim combo and same width of a 3.50 x 8 tire that i am using now -

And you wont!
There isnt one.

The options are:
300x8 stock
350x8 taller that all the rest/wider
110/80-8 wider still and not wuite as tall.
120/70-8 widest, which works and looks best and is the closest to stock diameter from all these sizes.

[Burgerman]

download/file.php?id=8284&mode=view

110/80-8 on a wider rim.

Same as:

[expresso]

Ok - does this mean i am stuck with what i have and cant do any better ? if i want to keep the width the same -

on a 2.5 inch rim from shirley -

would this be the size tire i would need ?

120/70-8 widest, which works and looks best and is the closest to stock diameter from all these sizes. - this would make the chair wider ?

i mean if i can do 27 inch - that should make a difference much i dont think from 26.5 now -

looks like my options are limited here - -

[Burgerman]

1 single 120 tyre is 120mm wide. Thats almost 5 inches. Yours are 3.5 inches.

Your chair would gain 1.5 inches per side! So 3 inches wider than now.

[Burgerman]

Like this:

3.00 stock...
and 120/70

[Burgerman]

or...
3.00 stock...
and 120/70

[expresso]

ok then thats too wide for me -


i am wondering now is it worth it for me to get rims and adapters if there are no real good options for me - i though having the rims from shirley and adapter with some kind of offset would make it so i can use a tubeless tire on a rim just a bit wider than stock rim - 2.5 inch and not have it stick out any wider than it is now -

i wouldnt want to do all this work for nothing - so my options are basically use what i have now with tubes or thinner 300-8 tire with tube also to try to keep the OD the same but would be thinner - the goal was to have a nice width on the rubber . 3.50 seems decent but lower OD would be nice and on those nice Rims shirley gets

all for the sake of trying tubeless and nice rims - or else i have to stick with what i have now and be happy

[Burgerman]

In the case of the Salsa chair, here, its width specs are:
Overall Width:
600mm (12.5" wheels)
620mm (14" wheels)

So it started at 620, with a 10mm gap to motor. (Thats 24.40 inches)
So reducing the gap to 3mm, means overall width could be 14mm less than this. So when I fitted the 120 tyres/wheels, I reduced this to 3mm.

So now we have, 620mm less 14mm = 606 wide.

Less 76mm for the old tyres from the 606 width each side is: 454
+120 for new tyres each side, means the chairs new width is 694mm. Thats 27.3 inches.

Actually the 120 tyres are not quite 120 so a little less. Ends up at a tiny fraction over 27 inches.

Your chair starts out wider. So will end up too wide.

So we deduct

[Burgerman]

On the salsa chair, which is just 24 wide to start with, adding those rims makes sense. Because its already 27 wide across the arms with my cushion/arms etc. So the new 27.3 width is the same as the arms. The wheels dont actually stick out at all.

[expresso]

ok i see - my chair was i believe 25.5 wide from the start -

i guess the only tire is a 90/90 - 8 if they make that size - that would give me 3.5 wide tire but may be too much sidewall then - ?

bottom line i am stuck with what i have unless i want to make the chair wider ? i though having the correct rim size would make the tire just not looked as pinched and flatter - i believe 2.5 inch is correct for the 3.50 x 8 tire or similar

getting rims wont solve anything in my case ? or improve anything

[Burgerman]

2.75 should be OK.

But yes, unless you move the motors IN by the extra tyre width, you cannot go wider.

90 is wider though by a couple of mm! But slightly less tall.
76 is the same as a 3.00 tyre.

This is just 25.4 wide.
Because to fit 145mm or 5.5 inch wide tyres, I moved the motors in by 3 inches each side.
http://www.wheelchairdriver.com/images- ... mp-car.jpg

[expresso]

ok so your suggesting a 2.75 inch rim with a 90/90 - 8 inch tire ? that would work with no other modifications ? may just be a few mm wider than what it is now - ?

i was thinking 2.5 inch rim - shouldnt that work better to keep it at the same width ?

lets say - i got a 2.75inch rim from shirley - with the hub adapter and a 90/90 - 8 tire - what would the outcome be more or less ?

i just need it to work with no modifications on my end - - other than adjusting the fender - thats fine - but cant move the motors etc, -

another thing - the screws on the hub - that the tire bolts down to - those dont need to be touched ?

[Burgerman]

I dont see a good way to fit the narrow rims at all. Theres no room for any adapter, the centre nut will be sticking out, it will all look a bodge...

A 90/90 tyre is 3.55 wide.
And is 90% of 3.55 tall. So overall diameter is 81mm x2 sidewall. So (81 x 2 div by 25.4 to give incheas, plus 8 rim, gives 14.37 diameter

The 350 is 3.50 wide, and 3.5 + 3.5 + 8 = 15 diameter.
The 300 stock tyre is 3 wide, 3 sidewalls, and 8 rim so 14 diameter.

[Burgerman]

I may add, that while its a size that is manufactured, its rare. I never saw one.

[expresso]

Ok so the best tire would be a 90/90 closet to stock just wider and would work on a 2.5 inch rims. ? But may be hard to find if at all. Maybe I am making a big deal for nothing and just stay with my stock rims tires ? I will try look for that size just to see what's out there curious. The rims would have looked nice maybe more trouble than itz worth. U don't think it's worth having shirly do the work and get rims ?

[Burgerman]

Not if you have to fit them backwards and have a nut sticking out of the middle. I wouldnt.

[expresso]

yeah - i wouldnt want them backwards etc, - i guess i put this to rest then - leave it alone the way it is - unless its broken i wont try to fix it - - the other user who made his stocks rims wider by adding a spacer between two rim halfs - he did a great job - that can be something i can try just to see - i have spare rims -

but i wont be able to do it myself - what would it take to do what he did - maybe half inch wider ? - that would make the tire fit nicer -

[Burgerman]

Not seen your wheel but maybe its easy. Maybe not.

[hobie1dog]

While we are talking 636 wheels and tires, my same stock setup measures 25 3/4" wide. I would love to get a tubeless tire that would be slightly taller and wider. I like the look of the 120/70 tires that were pictured. Are there wider wheels with more offset, which can be bolted to the stock hubs? I don't mind adding extra width to the chair.
Thanks

[Burgerman]

None I ever found. However if you cant make an adapter, shirley_hkg can do it aparently.

[expresso]

by adding an adapter - wouldnt that alone make the wheel about a inch wider ?

in that case a 2.5 inch rim or 2.75 inch rim with a bit wider tire would work - - at what cost to the width of the chair ? 28 inch wide ?

[expresso]

While we are talking 636 wheels and tires, my same stock setup measures 25 3/4" wide. I would love to get a tubeless tire that would be slightly taller and wider. I like the look of the 120/70 tires that were pictured. Are there wider wheels with more offset, which can be bolted to the stock hubs? I don't mind adding extra width to the chair.
Thanks

if you end up doing it - post some pics - i like the wide tires - but want to keep it at a min. if i can - your chair is the same as mines - size wise etc,

[hobie1dog]

None I ever found. However if you cant make an adapter, shirley_hkg can do it aparently.

I wonder if he can post up a drawing for us that I could take to a machine shop?

[Burgerman]

I have no drawing as such, but heres what you need to draw or make. viewtopic.php?f=2&t=7455&start=140#p114267

Scroll/read.

I ordered some laser cut alloy disks. And just used a pillar drill in my bedroom.

[expresso]

nice - this may not be the best thing for me to take on - even with shirley making the hub adapter and getting the rims - it may not end up as nice or too wide i believe afterwards - thanks for the facts and whats needed to get it done -

i recall shirley added the rims to his chair etc, but it didnt add any width over the 3.50 x 8 tire he was using before ? i think he went to 10 inch rims - but seems the same width from some pictures i seen a while back