fork cap will not budge

ST1100Y

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You'll usually feel a click of some sort as the threads align when turning it counter-clockwise, then reverse to clockwise and apply some pressure to the spring.
Exactly the technique I use to screw those caps (and other parts with fine threads) back on; provides fails safe aligning to avoid nicking/braking the first thread turns.
 

ST Gui

240Robert
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The tube is steel, and I think the cap is aluminum, so my guess would be the tube threads would survive and the cap threads are going to lose.
I thought that might be the case akin to spark plugs and aluminum blocks or drain plugs and aluminum pans.

At this point I'm curious as to what the cap looks like after the shop has tried to remove it with an air impact wrench. If it's in good shape maybe it'd be worth another go with the wrench.
 
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Dumb question maybe.....but I gotta ask...............why not drill the cap? When close to the edge/threads bend inward with a pliers....should peel right out of there..................ff
 
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Tip: [thanks Alan Hunt!] before inserting the spring, find the point at which the cap just begins to engage the threads, then back it off ~1/8" and mark the fork tube and cap with a Sharpie. Install the spring, match the marks up and screw in the cap. iPhone 4S
That's great Tip !!!!
 
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I had the same trouble only with both of them, I used a 1/2 air impact and zipped them right off.
be careful and don't put them back on with the impact gun.
Good Luck, Ride Safe
Dave


I've elected to change oil in my forks. and the left cap unscrewed without any real effort. the right not so much. I put both tubes back into the triple tree and tightened the pinch bolts..still the cap will not budge! i',ve gone as far as to cut a 1.5" length of 17mm allen wrench , insert it and then slip a box wrench over it( extended with a 12" section of pipe)...then turn(yes the right direction) while striking the allen section on top with a ballpeen hammer. still no joy. my Clymer manual says that these are assembled , using chemical thread loc. so I also tried heat, and penetrating oil too. outwardly the cap flange looks to be sitting on the tube, just as one would expect..and the same as the other tube is( the one that offered no resistance) anyone have some insight as to how to get this cap moving?
 

Nashcat

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Another thing to try. Since aluminum expands more than steel when heated, the plug will "grow" more than the tube when heated. So, maybe if you can put the tube in a freezer, or chill it with liquid nitrogen, the plug should shrink at a greater rate than the tube, thus creating some clearance between the threads. The ideal situation would be heating the tube and chilling the plug at the same time. Sometimes, drilling a large hole out of a plug will let it collapse a little and turn loose. I dealt with stuck threads for about 35 years, doing industrial maintenance work, and very rarely did we have to drill all the way out to the threads. Repeated cycles of heating/cooling along with frequent application of penetrating oil nearly always worked for me, even it it took a couple of days for the oil to creep in. Heat, cool, bang on it, oil it again. Repeat until loose.

Since I've retired, I don't get to do this on a daily basis, but last night I encountered a light bulb that is stuck in a lamp next to my recliner. Headed to the garage to look for the oil and impact wrench. :eek: :D

Wish you were closer. I'd like to try my hand at it.

John
 
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talking ome parts-37$ for the cap, and 220$ for the tube. doing any machining on the existing fork dictates that the complete strut will need to be rebuilt...and if you're doing one, most of us will go ahead and do both. frankly I don't have the time, I'm pretty well swamped with work and don't see it letting up until the fall. it makes sense to me to just reassemble and ride . ina month or three find a used set and rebuild them. after all this is my first time rebuilding these things and it always takes longer than one thinks it should..it would be nice to be able to ride while doing the work.( for once! & riding season is so short here) as far as the dealers work, I am sure they were afraid to really give it the "acid test". who wouldn't? when the manger came back with the fork he said that with "both of 'em holding the tube" they "couldn't keep it from spinning". I could hear the air gun going in the back room, what quality it was is anyone guess. they tried. I have worked on lots of cars and a few motorcycles so when I took the fork to a dealer, I was pretty sure it was a write off at that point.
 

W0QNX

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when the manger came back with the fork he said that with "both of 'em holding the tube" they "couldn't keep it from spinning". I could hear the air gun going in the back room, what quality it was is anyone guess. they tried.
If it was spinning on them then amount of force needed was not met. Pretty simple in my humble opinion.

It's going to need to be held either with the bike triple tree or a shop made bored clamp of some sort. Short version, the tube needs clamped in the fork and an impact used. Do as you were with the tube stick up so both top and bottom triple tree are holding. Those threads could possibly strip out if a "real" air impact wrench were hitting them.

If that fails then give up.

Raymond
 
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If it was spinning on them then amount of force needed was not met. Pretty simple in my humble opinion.

It's going to need to be held either with the bike triple tree or a shop made bored clamp of some sort. Short version, the tube needs clamped in the fork and an impact used. Do as you were with the tube stick up so both top and bottom triple tree are holding. Those threads could possibly strip out if a "real" air impact wrench were hitting them.

If that fails then give up.

Raymond
+1

see attachment, its good for about 800 ft-lb, those threads would have to give out long before the tool ran out of power. If we get 30 members to throw in $10/each we could add it to the ST list toolkit. But of course only those of us with air compressors could actually use it, but I think there's quite a few of us that have them.

Capture.JPG
 

Ron

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800 ft-lbs? That's a bit of overkill for most of the fork rebuilds. :D Not to rub it in, but mine came out with a 3/8 ratchet.
 

JPKalishek

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Remember too there are o-rings up there, so heating and adding oil isn't going to get much if any into the threads and too much heat is going to add a melted and charred rubber to the glue holding it in.
if the slider is still on, a possible way is to heat it inverted so some of the fork oil could possibly work its way in there.
If all the other works are off, filling the upper portion of the tube with Kroil and heating it with a heat gun or a careful flame then sitting some time might help, but from the sounds, it was hamfisted and possibly galled treads have welded it together.

A poormans impact is a breaker bar and a deadblow mallet or if more hit is needed a ballpeen hammer.
 

Andrew Shadow

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Another ideaa to try.
Drill multiple holes as close together as possible from one side to the other through the centre-line of the cap getting as close as possible to the tube threads on both sides. Drill it slowly with it turned upsidedown so that the drillings will fall downward and not in to the fork tube. Then take a chisel placed along the row of newly drilled holes and hammer it in to this row of holes forcing the cap to collapse in on itself along this line of holes. The size of the drill bit will be dependant on what size chisel you have available- you don't want the chisel to go right through the cap but rather to force the cap to collapse inward where it has been weakened by the holes. Once it collapses tap it away from the tube threads and remove. Clean it out before you turn it right side up to keep any drillings from falling in. Sometimes it may be neccessary to drill holes in a cross pattern to get it to collapse in quarters but not usually when dealing with softer metals such as aluminum.

Good luck.
 

MK92 MOD3

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Just got around to reading this. I'm around 60 miles from you. I have an impact you're more than welcome to use. I can't promis success, but I can promise a cold Pepsi.
 

ST Gui

240Robert
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;1730113]when the manger came back with the fork he said that with "both of 'em holding the tube" they "couldn't keep it from spinning".[/quote]

I'm in agreement that this wasn't enough. You've tired with the tube in the clamp and it still spun. The "professionals held it and the cap didn't loosen. Both instances lead me to believe that there's still hope for a monster breaker bar or my preference a powerful impact wrench. I'm thinking that the impact wrench might have worked (if it was a decent wrench) had the tube been solidly mounted.

Somebody tell me if this is a bad idea: clean the fork tube and inside of the triple tree with a degreaser or detergent. Dust the fork tube and inside of both triple trees with cornstarch and then tighten everything up. Not easy but if you can get some quantity of cornstarch between the ca T-clamps and the tube there might be enough "bite" to break the cap loose.
 

Nashcat

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I've had some good results using blackboard chalk on a shaft to increase the bite on a shaft. A single, thin layer of paper inside the clamp will also increase the grip.

With all the offers of help, this things gotta come loose before too long.

John
 
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I just did the same thing you are doing. It took way more effort than I thought it should. I slid the tube up 2 inches and used both clamps on the tree to hold it. I turned the bars to lock to give the impact something to bang on.It still took 30 seconds of hammering to get it loose.I was sure I was rounding the hole in the cap It Did distort the hex a bit but still worked fine . Good Luck . jp
 
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man, I feel for you guys. I've never needed more than a quick flick with a 3/8" ratchet.
 

ReSTored

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I'm preparing to change my fork oil in a few weeks, once the garage thaws out. This thread is scaring the %$%$ out of me.
 
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