Fitting rear axle to front fork

[ineria]

So the $500 questions is, how do I fit a 135 mm rear axle into the front forks which have a 100mm spacing? I'm assuming all (well, all cheapies at least) front wheels have the 100mm spacing and the rears are 135 mm (after all the instructions insist the spacing on the front brackets needs to be 135...no more no less). I figured the conversion accounted for this because 1) the instructions are specific that it must be 135 mm between dropouts 2) the donor page doesn't say to watch out for it 3) the kit page says "It sure does fit. The rear wheel complete with its gear cluster fits the front forks, to keep the all-important steering geometry."

So, I'm stumped. Any thoughts on the matter? Where do I go from here. I really didn't want to buy a new front fork. The only information I can find on front spacing was at sheldonbrown.com and it gave information on the front hub which in my mind translates to the fork spacing as well. Sheldon says modern bikes have the 100 mm spacing. I've checked this forum, but that's not been any help either...

 

[John Tolhurst]

We reverse the fork, add the brackets and voila. The rake built into all forks ensures the reversed fork plus bracket restores necessary steering geometry while allowing space for a 135 hub.

 

[John Tolhurst]

Its been mentioned numerous times on this forum, but searching for it is difficult since its all described with common language, unless you already know to search on "reverse fork" or "180 degrees"

 

[ineria]

Ok, I've looked around the forum searching using "reverse fork" and "180 degrees." It looks like most of the discussion is about getting the tire to fit underneath the fork crown and the other topics were unrelated. I have turned the fork around. The problem is, the hub (wheel) doesn't fit into the brackets and there is supposed to be a spacing of 135 mm between the dropouts (or with the conversion, between the FWD Brackets). Am I incorrect when I say the brackets I bolt onto the front fork are supposed to line up with the droputs on the fork? If not, then the brackets don't line up on the outside of the hub (where the axle slips into the dropouts) but is lined up with the gear cluster. It would be like trying to fit a 1.5 meter wide box through a doorway that is only 1 meter wide. If I am wrong, could you explain or point me to the discussion board that explains how you effectively widen the front forks? Please pardon my ignorance, but I'm really having a hard time understanding how turning the fork around and mounting the brackets makes the fork/bracket spacing wide enough to fit the entire hub with gear cluster. Thanks so much for the help!!

 

[JonB]

ineria wrote: Ok, I've looked around the forum searching using "reverse fork" and "180 degrees." It looks like most of the discussion is about getting the tire to fit underneath the fork crown and the other topics were unrelated. I have turned the fork around. The problem is, the hub (wheel) doesn't fit into the brackets and there is supposed to be a spacing of 135 mm between the dropouts (or with the conversion, between the FWD Brackets). Am I incorrect when I say the brackets I bolt onto the front fork are supposed to line up with the droputs on the fork? If not, then the brackets don't line up on the outside of the hub (where the axle slips into the dropouts) but is lined up with the gear cluster. It would be like trying to fit a 1.5 meter wide box through a doorway that is only 1 meter wide. If I am wrong, could you explain or point me to the discussion board that explains how you effectively widen the front forks? Please pardon my ignorance, but I'm really having a hard time understanding how turning the fork around and mounting the brackets makes the fork/bracket spacing wide enough to fit the entire hub with gear cluster. Thanks so much for the help!!

I suggest that you take a picture of your setup without the wheel, one with a quick release axle and one where you try to mount the wheel.

 

[defjack]

It should look like this.Back of bracket goes inside fork. Jack

 

[WhiteSilvio]

defjack wrote: It should look like this.Back of bracket goes inside fork. Jack

Note: the above photos are "upside down", or rather the bike was upside down at the time the photos were taken!!

 

[Mark B]

WhiteSilvio wrote:

defjack wrote: It should look like this.Back of bracket goes inside fork. Jack

Note: the above photos are "upside down", or rather the bike was upside down at the time the photos were taken!!

Pheeew! For just a second, there, I thought I was upside down!

Mark

 

[John Tolhurst]

Seemed ok from here.

 

[Gromit]

johntolhurst wrote: Seemed ok from here.

 

[ineria]

I think I found my problem…in trying to correct one I created another. I think the bracket is supposed to extend the opening an additional 35 mm. The real problem is the bracket doesn’t clear the bottom of my fork…so I padded out the space where the bolt goes with washers.

All this did was bring the brackets closer together so their spacing was also 100 mm. I think it’s just a coincidence everything lined up to look as it did. I think I can fix the bracket not fitting by extending the droput further downward with a piece of steel and drilling a hole through it for the bracket. Buy I'm concerned the bracket will be too close to the edge of the fork and will have a tendency to want to "slip off." I know the clamp should secure it, but it will still have that tendency (see picture)

These images should show up bigger if you download the file.

So, here it goes again

Thanks for the help so far!!

 

[Mark B]

Fit the brackets to your wheel first, then do what you need to do to fit them to the forks. That's what I do.

Mark

 

[ineria]

I think it's time for me to close out this help session. In the end, I was able to determine the problem was with the fork design and there really was no good way to work with it...risky at best and mostly impractical. So...I bought a new fork and replaced the old one. WIth the exception of the nipples sticking off the fork for the caliper mounts (which I needed to grind one off) everything fit nearly perfectly. Also, replacing the fork was FAR EASIER than I imagined

Went for my first ride today. too prideful to take it out on the road where the neighbors had a greater chance of seeing me make an arse out of myself. So, I tried it in the yard...BAD IDEA!!! Coudln't go 10 feet without nearly falling over or making a u-turn. When my wife went inside, I was actually rolling and then something (dunno what) threw me over sideways. I landed flat on my right side (in the grass) still in the riding position!! :lol: That was a fast fall... :shock:

Came back from lunch...neighbors not home...tried it on the road. After a few false starts, I was riding. Went down to the end of the road, negotiated a culdesack and back to my yard. I have to admit, I needed the entire lane...good thing no cars were around! I'll bet it looked like I was DWI. However, I'm now pretty good at riding in a straight line at an average speed of 12 MPH (my thigh is sore...remember?) and negotiating turns...startups are still embarassing though. So, 14 miles around the neighborhood and I was done for the night. The brain needs a break and time to process what it just learned today!! Educational theory says you need the night to burn the rough pathway into your noodle. Tomorrow I will work on refining my skills now that my noodle should know what's going on. BTW, NEVER practice two different but similar skills at the same time for the first time...your brain mixes it up and you'll suck and have a hard time with both (for example: learning to golf for the first time and swinging a baseball bat for the first time...they're too similar).

Thanks for all the help!!

 

[defjack]

Pictures are needed. Jack