jambon

Hi

I have a beloved Koga Miyata tourer which i picked up second hand a few years back .

The other day I went to change out the brake pads on the front Brake (cantis)

I had some trouble balancing the brakes on one side . Then I noticed that the rim on one side of the front wheel was much closer to the inner part of the fork than on the other side . This was stopping me installing the pads I wanted to use .

I suspected the wheel was out of dish so I changed it out for a different wheel of another bike but I still had the same uneven gap between rim and fork .

When I set the wheel in the fork I usually do it with the bike upside down so that gravity puts it in the right position in the dropouts . Then I tighten up the QR.

I have managed to correct it somewhat by pulling the axle on the leaning side back out of the dropout slightly so that it corrects the lean .

So .....questions .....

Is this normal for a front wheel to need to be aligned by hand like this ? I know Koga and Miyata have a good name in the bicycle world so I would have though the fork would have been made to precision and that dropping it into the deepest part of the dropouts on both sides means a centered wheel.

Is it possible to find a replacement steel fork for an old 22.2 headset taking frame ?maybe with a threadless steerer ?

Is there an issue with the fork that a frame builder or good bike shop could fix such as digging out a bit of the dropout to balance the wheel ?

Thanks again for any pointers,

J

Facanh

I worked at a bike shop where we mainly worked with vintage bikes. I've seen bent frames and forks almost every day. Even if a frame and fork is good quality, we are talking about 20-30 year old stuff here that has been through a lot. (I assume yours is not a newer Tourer?)

A frame builder or a bike shop that has dealt with similar things before could bend the fork back most likely by eyeballing it. If you feel confident you can have a crack at it too. Grinding the dropout is not really the fix. We bent back some lower end steel forks just by eyeballing it where the bike would pull to one side really really hard but tracked perfectly straight afterwards.

Yes, you can still find 22.2 forks, even new ones, and Columbus even makes a carbon threadless one, so there are definitely options.

If you don't have a tool to check the wheel dish rotate the same wheel in the fork and check the unevenness just to be sure. If it's really bad you should feel the bike pulling to one side without your hands on the handlebars.

jambon

thanks Facnah,

so how would I go about unbending the fork , would hand strenght do it ?

Any tips on where to soyrce a 22.2 fork ?

J

cny-bikeman

It is not unusual for a mass produced bike to not center the wheel when at the bottom of the fork dropout, so you can't assume that it's bent. With the wheel centered between the blades just sight down along the top and down tubes toward the wheel, on each side of the frame. It should look the same on both sides. If you can see the bottom part of the wheel/tire one side and not the other then the fork is indeed not straight.

jambon

Thanks ,

This sucks as the fork I have has eyelets for my tubus Tara lowrider rack , I reckon a replacement with eyelets will be hard find .

Besides an issue with brake alignment will having a bend in the fork effect how the bike rides ?

I assume the fork has been like this since I got the bike but i have never noticed it or had issues with tracking.

Bill Kapaun

Have you flipped the wheel to see if the same problem persists on the SAME side?
If the dish is not correct, the rim will be offset from the hub to one side.
If the problem remains the same amount on the same side, it's the fork.

jambon

If I go the new fork option will I have to figure out my headset type ?

My 1 inch headset could be JIS or some other type right ?

Will this effect the type of fork I can get or does that not matter as long as I switch crown races from old fork to new ?

Anyone know a good source of custom 1 inch threaded forks ?

Thanks .

Tried flipping wheel as suggested above , definitely frame issue , same problem on same side with wheel flipped .

j

cny-bikeman

I do not see that you have determined that the fork is indeed bent. It makes no sense to start worrying about replacement until doing so. It is common for a wheel to not center at the bottom of fork dropouts, even when a fork is properly aligned. You need to be aware that one is working in three dimensional space. The blades can be off to one side, one can be forward of the other, or the distance from crown to dropout bottom can be different. If only the latter is true then the fork is not a problem, and there is nothing wrong or at all unusual with adjusting the wheel when mounting. If you want perfect mounting at the bottom of drops then either order a custom frame or break out a file.

jambon

cny0- b ikeman ,

Thanks for your input

Interesting , The fork doesn't look bent .

When #I use the word "Bent" what I actually mean is it is out of alignment in some way .

I was under the impression that if a wheel is not perfectly centered when all the way back up in the dropouts then it is dangerous to play with the alignment of the wheel by edging it around in the dropouts as some argue here ;

What do you make of it ?

https://bicycles.stackexchange.com/q...-release-wheel

"You must not try to align the wheel to the bakes, the wheel is just pushed all the way in the dropouts and tightened. If your brakes are misaligned, you fix the brakes:"

"
As others mentioned, do not try to manually align your wheel to the brakes (rather, adjust the breaks). Also, you might want to make sure that your wheel is dished properly (the rim is centered about the hub correctly)."

jambon

Some more conflicting info from this older thread

https://www.bikeforums.net/bicycle-m...alignment.html

"Front wheels should not need any positioning in the dropouts. Just stand the wheel vertically, lower the fork onto the axle so the axle is all the way into the dropouts, and fasten the QR while bearing weight on the stem to ensure that the wheel's all the way into the dropouts. If the brake is rubbing afterwards, then either the brakes need to be adjusted using the spring-tension adjusters or centering adjuster, or your front wheel has a dishing problem, or your fork is out of alignment. HTH "

"If your fork is out of alignment you can file the drop to correct it (tiny amounts and test often). Or you can shim the other side. I used double sided tape and a thin piece of plastic (from a battery blister pac) for one bike until I could get around to filing the other side. That was ages ago and I never got around to filing it."

cny-bikeman

It was my error to continue your use of "bent" rather than out of alignment. In many cases one can only tell if a fork is out of alignment by measurement or by careful observation, an example of which I gave above. Another "eyeball" test one can do is to place the bike upside down, mount correctly dished wheels on the bike without tires mounted and centered between fork blades and rear stays. Site along both sides of the front wheel, first toward the top and down tubes and then toward the rear wheel. Everything should be parallel and appear the same on both sides.

Your impression is wrong - it's in no way dangerous to align the wheel by moving the axle in the dropouts. Again, it's COMMON to do so on lower end production bikes, even with a fork that is not out of alignment, and if necessary one can indeed correct minor errors by filing the dropouts.

What I make of the comments on that thread is that they are poorly informed and poorly written. One first aligns the wheel so that it is centered in the forks. That of course assumes a correctly aligned fork and dished wheel. Then one adjusts the brakes so that they are centered on the wheel. After that when reinserting the wheel one does indeed center the wheel on the brakes, as long as they are still properly centered. As for the statements that "A quick release (front) wheel should just sit at the top of the dropouts, and be centered", or "Front wheels should not need any positioning in the dropouts." see my comment in my signature line below about should.

If you can center the wheel by adjusting the position in the dropouts and the fork/wheels are then properly aligned then filing the correct dropout should allow you to simply bottom out the wheel to center it.

Finally, if your fork blades are out of alignment it usually takes removal from the bike, leverage and accurate measurement to properly align it. Although I managed to field-align a fork that was bent when my bike fell off a roof rack, with no tools or gauge, and rode a 200 mile ride afterword, such work should be given to a shop - although I don't know how many these days are too scared to do so, or don't have the right equipment/experience.

p.s. I worked professionally on bikes for over 20 years, and I can tell you that mechanics routinely remount wheels with the bike still in the stand, not on the floor. The wheel is first inserted all the way into the dropouts, but if it does not center between the blades we move down an axle end as needed to center the wheel, and then tighten the wheel in the dropouts.

jambon

Thanks again bikeman for clearing that up,

When the axle is backed all the way into the dropouts and locked in witn the Qr I cant slide my finger between the fork and rim on one side but very easily with lots of extra space on the other .

Eyeballing the fork it seems normal , no crazy bending.

Dish of wheel is perfect , tried it in another frame and tried a different wheel in the fork in question.

Playing with the axle in the dropouts I can balance the wheel so that it isn't so close to the fork on one side .

Long term i will look at filing down the dropout so that it bottoms out with the wheel centered

cny-bikeman

Sounds good. BTW it may be a good idea to check dropout alignment to make sure that's not affecting things.

SquidPuppet

+1

Dropout alignment can cause exactly what OP is experiencing. Frustrating as heck.

OP, IF it is a dropout alignment problem, the repair is easy and quick. You can even do it yourself.

fietsbob

each blade has 360 degrees that it could be out of place.. problem is the reference guide of what is straight, is a shop tool,,
one works only with the fork out of the bike, the tip alignment tools are just needing the wheel removed..

Cost of these tools = the cost of your bike, so the shop fee to have this done, relatively, is pretty cheap..

jambon

Thanks , how would I go about that ? Is it two threaded screws and a few washers that should meet in the the centre of fork ? I think rj the bike guy has a video on YouTube doing something like that

fietsbob

have to make the tips parallel to the bike center-line.. 4 nuts, 2 axles, or all thread stock can work, cut in half .. if the tips are in plane

the 2 ends will be straight inline in the center..

But 1 blade can also be bent ahead or back relative to each other, then the tips can be parallel, but the 2 sections of the threaded stock will not be aligned, but one ahead of the other..

twisting the dropouts can cover up that symptom ..






..

AnkleWork

How much off center, in mm?

I have a trek "system" fork that is visibly offset from new. It's a very stout fork and has never caused problems (only ~20k miles). I just setup the brake pads off center and ride.

Andrew R Stewart 

https://www.bikeforums.net/bicycle-m...ulls-left.html


This is a good thread covering fork alignment. Check out my post, #16, for simple home methods. Andy

jambon

Has anyone a clue as to what the minimum drop out thickness should be before attempting re alignment ?

I read on dropout alignment park tool page not to try this on thicker drop outs or on forks that don't have a narrow section between forkblade and dropout