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Front Axle Alignment Issue


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After not having a bike for a while I just recently picked up a 2007 CRF450. I was doing some general maintenance to the bike to get it ready to ride and had to remove the front wheel. When I went to re install the front wheel, the front axle would not sit flush with the pinch clamps on the right fork. I followed the instructions of re installing the front wheel very specifically. First, I torqued the axle nut. Then I tightened the left fork pinch clamp bolts. I then grabbed the front brake and pumped the shocks to seat the axle and fork properly. The result every time was the axle recessed into the right fork about 1/4 inch. I can physically press the fork over a little bit so it sits flush with the axle and then tighten the pinch clamp bolts, but that makes me a little worried that my forks might not be aligned properly. Is this an issue that any of you have had before? I dont remember ever having this problem with my 2002 CRF. Thanks for the help.

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Edited by SubyDude05
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Dont know specifically about your bike, but I used to play with the fork leg, pushing it one way and then the other letting it come back to it's "natural" position before tightening the clamp bolts. I finally bought the Motion Pro Fork Alignment tool and like using it, feel like it was worth the price for the assurance that my forks are aligned.

....

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One test you could make would be to rotate each fork 90 or 180 degrees in their clamp and redo the bounce test as you have done. If it changes the way the axle sits, rotate the fork back to its original position and see if it stayed as it was or went back to where it is here. Such a thing would point to a bent tube.

Alignment in the clamps can be checked by removing the wheel and fork guards and laying a piece of glass or other verifiably flat plate on the inner tubes.

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Well the bike has pretty low hours on it according to the previous owner. And there is an aftermarket wheel and hub set on the bike. So possibly it has wrong spacers or something? Where would I go from here to find out what the issue is? I would hate to think the bike I just bought has a bent fork...

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it doesnt have to sit flush i mean it should be close but they dont always sit flush. my bike the axle sits about 1/8th inch into the fork.

good way to check you for alignment is to make sure your axle is good and free inside the the clamp...if not sand it down with a peice of emry cloth till the bolt slides freely in and out of the right fork leg. then put it all together and tighten you nut to spec. loosen up the pinch bolts on the right fork put the bike on a stand where the front wheel is off the ground. make sure your fork now slides back and fourth on the axle freely with the pinch bolts loose. put it to the most natual position. spin your front tire and then reach up and grab your front brake real hard making the tire stop rotating abrubtly. do this a few times. then tighten you pinch bolts but be carefull not to move the fork any.

your ready to rock! lol

Edited by rpxtreme03
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One other tell-tale thing would be the threaded end of the axle. Assuming the axle itself has not been shortened, how does the amount of thread standing out above the nut compare to another bike like yours with a stock wheel? A larger amount of exposed thread would point to a short spacer on one side or other. A normal amount of exposed thread would point to splayed fork tubes.

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In order to see if my forks were bent, i rotatated the forks 90 degrees and re installed the wheel. The axle was still recessed into the fork the same amount. This leads my to believe that it is the hub and spacers that may be the issue. I contacted the previous owner of the bike and he said the new hubs did require different spacers, which were installed. Could the axle just sit a little differently with an aftermarket hub?

Like i said before, i can physically push the right fork into the wheel to make it sit flush, but this will put lateral stresses on the fork tube.

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I

Like i said before, i can physically push the right fork into the wheel to make it sit flush, but this will put lateral stresses on the fork tube.

You dont want to do that. The fork wants to be in its happy relaxed place. If you force it over and snug the pinch bolts it'll bind up huge on compression. Ive seen them stick up there. Guy comes rolling into the pit with a brand new front tire and the fork stuck half way down in the stroke. Pretty obvious what happened.

If the fork doesnt feel sticky after you get it set, its ok.

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One test you could make would be to rotate each fork 90 or 180 degrees in their clamp and redo the bounce test as you have done. If it changes the way the axle sits, rotate the fork back to its original position and see if it stayed as it was or went back to where it is here. Such a thing would point to a bent tube.

Alignment in the clamps can be checked by removing the wheel and fork guards and laying a piece of glass or other verifiably flat plate on the inner tubes.

This was the same issue I was haveing awhile back regarding a Spyder EVO disc guard I was useing. The axle would recess back in the hole a 1/8 or so after tightening everything up. Look at this thread(all though the image has been deleted I put up) but it was like SubyDude05's above but not that bad.

https://www.thumpertalk.com/topic/881325-spyder-evo-disc-cover-on-2010-450/page__fromsearch__1

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I'm at work and can't see any photos so maybe I'm way off base here.. It sounds from your description that the forks or the wheel spacer combo is not even close to being correct. I can't envision a circumstance where being able to squeeze the forks together once the wheel and spacers are in place as being a good thing.

With the front wheel off you could measure the distance between the fork centers at the lower triple and then down near the axle. The distance should be the same or damn close. Then you could measure the inside gap at the axle blocks and check that against the width of your front wheel with spacers installed. They two measurements should be every close as well.

Or am I completely misunderstanding the issue? No pics here on the work PC. (hey, I am working, I monitor our network, and it's fine. ? )

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How is the rotor spacing in the caliper? The axle is pulled up against the wheel spacer so it *could* go in a little as long as the spacer between the wheel and the left fork casting allows the brake to line up properly. Definitely do NOT pull the right fork flush with the axle just to keep it flush.

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I'm at work and can't see any photos so maybe I'm way off base here.. It sounds from your description that the forks or the wheel spacer combo is not even close to being correct. I can't envision a circumstance where being able to squeeze the forks together once the wheel and spacers are in place as being a good thing.

With the front wheel off you could measure the distance between the fork centers at the lower triple and then down near the axle. The distance should be the same or damn close. Then you could measure the inside gap at the axle blocks and check that against the width of your front wheel with spacers installed. They two measurements should be every close as well.

Or am I completely misunderstanding the issue? No pics here on the work PC. (hey, I am working, I monitor our network, and it's fine. ? )

your way off haha he is saying with his pinch bols loose the right fork will slide freely to sit flush but that is putting it ou of alignment. like i said befor these dont always sit flush on every bike. some stick out a little some are slightly inside. it could just be some one beat the end of it down and then ground it off to clean the end up. clearly your fork tubes are not bent and you have the right spacerin there if your brake rotor is lined up properly. are you missing the spacer on the right side?

its something to the right of the wheel. either the hub itself is short, its missing the spacer on the right side, its got the wrong bearings, or somebody gound the end of the axle off because it was peaned from some smoke driving it in with a hammer.

my 06 crf250r sits in about 1/8th of an inch or less. obviously far less than yours does but its not like it makes it any more prone to coming loose. just keep your pich bolts tight as usual.

if your too worried about it to ride try a new axle. it never hurts to replace the axle anyways.

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your way off haha he is saying with his pinch bols loose the right fork will slide freely to sit flush but that is putting it ou of alignment. like i said befor these dont always sit flush on every bike. some stick out a little some are slightly inside. it could just be some one beat the end of it down and then ground it off to clean the end up. clearly your fork tubes are not bent and you have the right spacerin there if your brake rotor is lined up properly. are you missing the spacer on the right side?

its something to the right of the wheel. either the hub itself is short, its missing the spacer on the right side, its got the wrong bearings, or somebody gound the end of the axle off because it was peaned from some smoke driving it in with a hammer.

my 06 crf250r sits in about 1/8th of an inch or less. obviously far less than yours does but its not like it makes it any more prone to coming loose. just keep your pich bolts tight as usual.

if your too worried about it to ride try a new axle. it never hurts to replace the axle anyways.

Now I can see the picture. ?

The fact that the big end of the axle sits a bit recessed wouldn't bother me. However being able to push the fork over enough with the wheel installed to make the axle sit flush would make me want to check some things. Seems like that would indicate a lot of slop between the wheel spacers and forks. If it were mine I'd want to know if that was due to an issue with the spacers or the forks.

Edited by Windblown
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...being able to push the fork over enough with the wheel installed to make the axle sit flush would make me want to check some things. Seems like that would indicate a lot of slop between the wheel spacers and forks. ...

Next time you have your front wheel off, grab the bottoms of your forks and see how easy it is to move each one an inch toward or away from the other. That ease of deflection at full extension is why the method of bouncing the bike against the brake is recommended; it's just too easy to misalign them otherwise. For anyone who hasn't figured out why it works, compressing the fork increases the overlap of the telescoping assembly, which makes them more prone to center themselves up.

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Next time you have your front wheel off, grab the bottoms of your forks and see how easy it is to move each one an inch toward or away from the other. That ease of deflection at full extension is why the method of bouncing the bike against the brake is recommended; it's just too easy to misalign them otherwise. For anyone who hasn't figured out why it works, compressing the fork increases the overlap of the telescoping assembly, which makes them more prone to center themselves up.

Edit: Duh... I see where my thinking we messed up. The shoulder of the axle is snug against the spacer regardless. Therefore there is no side to side slop. Geez I'm thick sometimes... LOL

Edited by Windblown
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UPDATE:

So I rode the bike on Friday with no real issues but the front wheel is still a concern of mine. The front disc will spin freely in between the brake calipers with no sign of wobble. I just send DNA an email explaining the issue to them so I will wait and hear back what they have to say. I am thinking now it could either be the bearings in the wheel or simply the wrong spacer set for the wheel. It would seem like it may be the spacer on the left side of the hub that is too small, thus causing the wheel to sit a bit left then causing the axle to recess to the left side? ? Or do the DNA wheel sets just sit differently in between the forks? I will get to the bottom of this!

Edited by SubyDude05
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