Steering head or fork lock - 73 TX

[wesleyonoel]

Been fiddling with the fork lock mechanism on the steering head - left side. Am able to insert ignition key without any problem. Can turn tumbler with key inserted (CCW) about 1/4 turn but fork doesn't lock. Resistance to further key rotation is felt at that point. Must turn the key back to starting position to remove but the locking mechanism doesn't engage. I have sprayed cleaner then lubrication in the key slot followed by a blast of compressed air to force liquids as far in as possible. Doesn't seem to have loosened anything. Any ideas/experiences? In the mean time I'll continue to periodically lubricate and operate the tumbler with the idea eventually something will loosen and start working..............Thanks in advance for any information you pass along.....Wesley

Jumped B4 searching archive. I think I have my answers..........Thanks gents....Wesley

 

[5twins]

Usually, you need to turn it that 1/4 turn, then push it in before you can turn it the rest of the way.

 

[wesleyonoel]

Usually, you need to turn it that 1/4 turn, then push it in before you can turn it the rest of the way.

5twins
I think the mechanism is in need of a good cleaning. The more I fiddle with it, the better it seems to work. Still can't push it in as you suggest but will continue along that line. Thanks for your suggestion.............Wesley

 

[xjwmx]

Take it off and take it apart and give it a good clean and lube. Burnish the electrical contacts and grease them too. You won't be sorry. Don't use WD-40, because it turns to gum in a couple of months and will just make things worse.

 

[5twins]

You have to have the forks turned to just the right spot in order to be able to push the lock in. The lock pin needs to align with the slot in the stem. And it's not at full lock as you might think, it's a little before that.

 

[wesleyonoel]

xjwmx, 5twins
I have mechanism out of the stem. Just now sorting through how it all works. And as you suggest 5twins, the fork lock actuates B4 reaching the limit or full-stop position of fork rotation to the right. After I get it sorted, I'll clean lube (probably dry graphite) and reinstall. Thanks gents...............Wesley

 

[xjwmx]

(probably dry graphite)

You don't want to use graphite around electrical contacts, since it's conductive. I just use general purpose auto grease. Best is marine grease if you can find it, since it's less prone to washing out. They use it on boat trailers, that get submerged. In addition to the mechanical parts, coat the contacts after sandpapering, and inspect the solder joints to them, and maybe redo. It can keep your bike from turning off at an inpportune time...

 

[XSLeo]

On the early bikes the fork lock is on the steering neck. It is not part of the key switch.
Up to 77 I think were that way.
Leo

 

[xjwmx]

Ha! It's not the first time I've been guilty of assuming all the years are like mine.

 

[wesleyonoel]

As XSLeo suggests, the locking mechanism is located on the left side of the steering neck - no electrical connections present. On my '73 TX (bone stock) the ignition key operates the fork lock as well (seems I saw that question somewhere?). Internal cylinder separated from the surrounding/corresponding outer lock sleeve which I don't think is supposed to happen. Looks like a roll pin let go internally? I think the 1/4 turn chrome lock access cover must be removed to correctly remove the intact mechanism. There appears to be a fastening "tab" - part of the outer lock cylinder sleeve - secured and indexed between the cover and neck "boss". Still studying that as the cover is held in place by a peened round headed rivet with a spring-type tension washer between the rivet head and cover. Not sure how the rivet might be fastened to the cast iron of the steering neck at this point. Before removing the rivet, I thought I'd ask if anyone has encountered this problem and what a good solution might be. I suppose I could tap (thread) the cast "boss" then reinstall the cover with a screw? Looks to be the only way to properly service the internals. Might be in for some fabricating too. I think the outer lock cylinder sleeve where the lock pawls index might be cracked/broken. Goofy the things a chap will get involved in with these relics! It all started out innocently enough....... Intent is to have everything functional even if not integral for day-to-day riding. Thank you in advance for any help, knowledge or experience you may pass along..............Wesley

 

[xjwmx]

I think you're asking how to get the cylinder out of the lock? I think I remember on mine you just pry down on the last tumbler, from inside. Of course this is probably just for my year If the key is inserted when you pull it all out it helps keep it together.

One thing is for certain though; you don't have to do any metalwork to get the cylinder out. The department in charge of keying would have flown into a rage if they'd done that...

 

[wesleyonoel]

xjwmx
The guts (cylinder and pawls) are out of the steering head and on the bench. The locking sleeve (much like an inserted engine cylinder sleeve in a cast iron block) is still in place. Maybe I don't have to remove it at all but looks like that's the only way to insert the roll pin at the base of the cylinder which seems to serve as a index/locator and rotational limit stop between the cylinder and sleeve. I've decided to stop for supper and think about a little more B4 diving back in. Oh, keeping the key in the lock indeed helps keep everything together - you're right!........But for all the world it looks like the whole works is held in place by the rivet/pivot for the 1/4 turn lock cover........

 

[xjwmx]

^I can't picture what it is you're trying to do then, but that's probably because it isn't like mine and therefore I wouldn't be much help anyway One thing I don't like about mine is the locking bolt is turned by a piece of molded nylon that looks strippable. But so far so good.

 

[wesleyonoel]

Would be much better if I had a way to add photos to my narrative, I'm sure. There are no nylon pieces in this particular mechanism - all metal. The roll pin is inserted near the base of the cylinder at a 90 degree angle to the long axis of the cylinder. It protrudes out of the cylinder just enough to locate the cylinder inside the surrounding sleeve which in turn has "ways" to allow the cylinder to rotate inside the sleeve using the roll pin as a guide. The cylinder/roll pin assembly can't be inserted while the sleeve is in place in the cast iron boss of the steering head - no clearance. If the sleeve (outer wrapping of the lock mechanism where the pawls index thereby stopping the cylinder from turning in absense of a key, if you will) was removed from the steering head boss, the cylinder could then be inserted inside the sleeve, roll pin installed in its 90 degree position (in essence marrying the cylinder and sleeve together) and the entire assembly could then be slipped back in the cast iron boss as a unit. Then by inserting the round headed rivet through the tab of the sleeve and 1/4 turn lock cover, the sleeve would be captured in the steering head boss unable to turn - only the cylinder could turn inside the sleeve once the key is inserted releasing the pawls from their indexed positions. I can imagine this would be very difficult to follow without a photo or diagram so apologize for any confusion I've caused. It's about as clear as mud to me anyway. Besides, it's not a life-threatening problem - just a nuisance issue. I'll eventually get it sorted out and will then quietly return to the sidelines. Thanks for your willingness to participate. It sometimes helps to just "talk" through a problem.....................Wesley

 

[5twins]

I was wondering how you got it apart. I've had all the locks on these apart - except that fork lock. I could never get that one apart.

 

[wesleyonoel]

5twins
I'm relatively certain the round headed peened rivet must be removed to extract the entire mechanism intact. Unfortunately the internal roll pin between the rotating cylinder and outer indexing sleeve let go. Not sure what kind of repairs will be required to reassemble correctly as I still haven't removed the rivet. Probably be a good idea to replace with another rivet when the time comes since a screw would allow easy removal of the locking mechanism thereby defeating the purpose of the lock. Looks like that's what the designers had in mind?.........Wesley

 

[XSLeo]

I don't worry about the fork lock. I have two big Master Padlocks, One on the rear sprocket and one on the front disc and it won't roll away. Picked up and carried away but not rolled away.
Leo

 

[mouser]

the only way to get the whole mechanism out it seems is to remove the rivet. I just ground it off a lock mechanism I had cut off my frame. The rivet appears to have splines on it that are a friction fit in it's hole.

 

[wesleyonoel]

XSLeo, mouser
Well, this whole thing started for no real good reason. May never use the darned thing once it's returned to service. Never have felt compelled to lock the forks for security purposes - just an attempt to have everything on the scooter functional. I seldom leave it parked anywhere - it spends most of it's time here in my shop. Besides, as you suggest XSLeo, if they want it, they'll take it!......

Thanks mouser for your contribution. It has confirmed my suspicion the rivet must be removed to extract the locking mechanism in one piece. Stopped by a friends engine machine shop to discuss the rivet and he thought it must be as you describe. Similar fasteners are used to secure engine valley pans. We thought we'd cut the original off then fashion a stainless steel interference fit piece (maybe splined and tapered?) on the lathe as a replacement. You have provided the "key" to the last remaining piece of the puzzle........Thank You!

If the lock mechanism is still functional, would you be interested in selling the remains you removed from you scooter? I might be in need of some of the internals. Either that or I'll spend some additional time at the lathe.......

Thanks gents for all your input. This has been fun in a weird sort of way...........Wesley

 

[mouser]

I doubt any of it is of any use because of using a disc grinder to remove it, but if it is of any use to you it's yours.