How To: Rekey Your Seat Lock

Vlad

XS650 Enthusiast
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Hi all! I re-keyed my seat lock successfully using this method and wanted to share it here. This worked for me on an '80 XS650SG. I'm not sure which other bikes use the same type of locking cylinders. I'm also not familiar with a lot of the specific terminology, so please forgive me for mis-descriptions of any of the parts.

First I removed the seat lock from the bike and then removed these two screws from the back:

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Next, I removed the helmet latch spring body:

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Next, I removed the seat locking pin and this other part. Mine was pretty gunked up so the parts stuck together. Be aware that there is a small pin and ball bearing here that would be really easy to lose if you dropped it somewhere so proceed with caution.

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Here is that ball bearing. To remove the lock cylinder, push the brass slider thing (blue arrow) just enough so that it clears the bore of the lock body. Then the cylinder should easily be removed from the key side.

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When you take it out, it looks like this (top). When you put your key in, it looks like this (bottom). Notice how the tumblers moved to random places. Also note their numbers, we'll be using this later.

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So the first thing you'll want to do is find any of them that match the key in any of the five positions. In my case, 2 of them were a perfect match (numbers 1 and 5). Place the matching ones in their place and leave them there. If you don't have any matching ones, don't worry.

After moving them around, this is the best I could come up with. The circled blue one was just barely peeking out so I filed down the top just a little bit. The ones circled in red are obvious no-goes so we'll need to work on this. VERY IMPORTANT: When moving your tumblers around place them such that you maximize the number that are either a perfect match, or they are low. It'll be much better to have 2 that are low than 1 that is perfect and 1 that is high. Low/High is in reference to the locking slider that holds the cylinder into the body. It's all the way on the left in this pic and protrudes towards the top. Low means the tumbler is going down and high means it's going up.

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Now, the reason that you want to go with as many low as possible, is that you will basically be filing down the inside of the tumbler to shift it up.

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Since each tumbler is on a spring, inserting the key simply displaces it by how deep the key is cut in that position. Therefore, if the key is not cut deep enough, we can make up for it by removing some material from the tumbler. To shift them down would mean to add material to this piece. I'm not quite sure how I would do this, perhaps soldering a piece of brass or copper to it and then filing it down to the correct size. But if I had any left over that I had to shift up, I would have probably simply discarded them. 4/5 or even 3/5 is good enough for me; I don't honestly believe that changes the probability of my helmet getting stolen or the bike being vandalized.

Now be careful! Don't file off too much at a time. Go little by little, reinserting your key to check that you haven't gone too far. Here are the results after filing the two pieces of mine that were low:

Top pic shows #3 fixed, bottom pic shows #3 & #4 fixed.

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Once you get to this point, you're done. Just clean everything up, lube it really nicely (I used white lithium on everything inside the body and a graphite lube on the inside of the key hole), and re-assemble.

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A normal local key shop won't be able to make a key because they won't have a blank... Locksmith Parkland can make scooter keys may be able because they take a similar blank. As for a new ignition, they should be able to order one for you. I say "order" because it's not a part they are likely to have in stock.
 
Good explanation Vlad. You technique will also work on Honda locks as well.
I recently had the seat lock on my bike apart for cleaning/rebuilding. Different design but same lock tumbler.
xs650c_rebuild_seatlock_59.jpg xs650c_rebuild_seatlock_58.jpg
Do not lose those any of those tiny springs!!
 
Very nice "how to" thread.. Should be a sticky or at least linked to in the frame and body part of the "tech" section.
 
Yes, this is good, and the funny thing is, I don't recall seeing it when it was first posted. I was going to do a thread on locks but this pretty much covers it, although I may add some things.

I scrounge the locks off of parts bikes and out of my dealer's bone yard for the extra sliding plates. I've re-keyed several locks and haven't had to file any plates yet. I had the proper "spares" from my scrounging efforts. Obviously, you have to get the lock out to do this job, but that's usually not too difficult on seats, gas caps, and ignitions. The one I haven't been able to "crack" yet is the fork lock. I picked up a new one off eBay so I have it for reference and to see how the thing operates. There is a roll pin through the cylinder that turns with it and that appears to be what holds it in the frame. The only way to withdraw the lock assembly is with it in the "open" position, so you need the right key or you have to "pick" the lock. I haven't been able to do that yet on the one I'm fooling with but even though that parts bike is stripped and going to the bone yard, the fork lock is not .....

T2626DB.png


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I'll get that sucker yet, lol
 
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I meant to mention to you CR, get in the habit of checking the two little mounting screws for your helmet/seat lock. They like to loosen up, then the part falls off never to be seen again. My buddy has lost two or three of them already, but he's not much for checking things on his bike. Mine was missing when I got my 650 too. I scrounged one, re-keyed it to match my key, and I've had it ever since. I do check the mounting screws often and I do find them a bit loose many times.

The last time my buddy had to get a replacement, he bought it from another local 650 guy. It cost him $20. I'm hoping maybe he's learned his lesson now. Your wallet can be a good teacher, lol.
 
Me, I just rip the plates out and file the jiggles out of the keyslot so the lock will work with a screwdriver but I ain't living in a high crime area.
That said, here's a trick to help keep all those fiddly little parts from disappearing when you work on small items
like carbs, instruments, locks or whatever.
Do the work inside of a cafeteria tray (or anything similar with a raised edge all round it) so those escaping parts
can get as far as the boundary wall but can't climb over it.
 
Hi weaselbeak,
I DO get ignition and gas cap keys made. My locksmith has a sliding scale.
Take a key in and he has that blank in stock, $3 a copy.
No blanks in stock, a $20 re-stocking fee then $3 a copy.
Take in just the number on the lock, that get's expensive.
 
My new neighbor is a locksmith. He had no idea what he was getting into! His work just help turn a "parts radian" back into a runner that sold to a new owner.
 
I've been doing some research into the various key blanks used on these bikes. The ilco catalog only goes back as far as 1980 but it does mention the XS model (not specifically the 650) and shows 6 different blank styles .....

ixrnjH6.jpg


Here's what they look like .....

p2zxuHs.jpg


So far, on the mid to late '70s Yamaha models I've had access to, I've only run across X117s and X118s. Maybe members with early (2Many?) and late (Fred?) models could check their keys and post the types?
 
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Sorry, can't help here. Ditched my XS locks and keys eons ago.
All I have is a box of '70s Honda keys (necessary when customers forget to leave their keys with the shop)...
 
Good explanation Vlad. You technique will also work on Honda locks as well.
I recently had the seat lock on my bike apart for cleaning/rebuilding. Different design but same lock tumbler.
View attachment 86173 View attachment 86174
Do not lose those any of those tiny springs!!
I have the same style lock on my 1980 xs650 and can't figure out how to take it all the way apart to re key it because I don't have the key for it. Have any tips or tricks to get it apart?
 
I take it you're dealing with a seat/helmet lock like this? .....

SYcNkTT.jpg


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You'll have to remove the unit from the bike to disassemble it but as you can see, the screws that hold it on go through the top. To get at them, you have to have the seat open, and you can't do that without a key. So, you're going to have to pull the lock cylinder out of the assembly with it still mounted on the bike. Then you can stick a big screwdriver in there and operate the functions (seat and helmet locks).

If you look at the first pic in the first post that shows the lock cylinder, the one with the plates numbered, notice that other plate to the left of the numbered ones. That's the one that holds the cylinder in the housing. It's at the very bottom of the cylinder, past all the actual "lock" plates. You'll need to reach into the key slot with a long pick or strip of sheet metal and slide that last plate up or down to release the cylinder from the housing. I'm not sure which way you'll have to move it, up or down. That will depend on how it's installed in the housing. You'll figure it out by trial and error.

Handy little lock picking tools can be made from the stainless steel strips pulled out of old windshield wiper blades (tip from gggGary). The 3rd one up from the bottom, the one with the little "bump" on the end, works well for sliding that last plate and releasing the lock .....

4Ro71l8.jpg
 
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5twins if it is already off the bike don't you just lift the keeper plate and it will slide out the key side?

seat lock.jpg
 
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I take it you're dealing with a seat/helmet lock like this? .....

SeatHelmetLock2.jpg


You'll have to remove the unit from the bike to disassemble it but as you can see, the screws that hold it on go through the top. To get at them, you have to have the seat open, and you can't do that without a key. So, you're going to have to pull the lock cylinder out of the assembly with it still mounted on the bike. Then you can stick a big screwdriver in there and operate the functions (seat and helmet locks).

If you look at the first pic in the first post that shows the lock cylinder, the one with the plates numbered, notice that other plate to the left of the numbered ones. That's the one that holds the cylinder in the housing. It's at the very bottom of the cylinder, past all the actual "lock" plates. You'll need to reach into the key slot with a long pick or strip of sheet metal and slide that last plate up or down to release the cylinder from the housing. I'm not sure which way you'll have to move it, up or down. That will depend on how it's installed in the housing. You'll figure it out by trial and error.

Handy little lock picking tools can be made from the stainless steel strips pulled out of old windshield wiper blades (tip from gggGary). The 3rd one up from the bottom, the one with the little "bump" on the end, works well for sliding that last plate and releasing the lock .....

Tools-Picks.jpg
5twins if it is already off the bike don't you just lift the keeper plate and it will slide out the key side?

View attachment 90665
The lock is already off the bike and I've taken the keeper plate off and the lock has not slid out of the housing. Any directions on how to get it out/troubleshooting I should do?
 
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