Clutch basket not "tight" enough?

[lidirtrider]

So after seemingly having no compression, amd searching here for tips, i find that I have a clutch issue. I pulled the RH case cover off and when I turn the kick lever, I can see the metal plates rotating inside the clutch basket. It is a,somewhat, freshly rebuilt enigne that hasnt been started yet. Installed all new friction and drive plates from MikesXS, and used the Mikes/XS Performance clutch springs with the aluminum sleeves and allen bolts.

I should also note that this issue was happening before I even put oil in the engine and before I had a clutch cable and worm gear hooked up.

Is it possible that the aluminum sleeves were too long? I've read a lot that the springs that Mikes provided were not the best either. It just seemed that there wasnt enough pressure on the pressure plate to get a good luck-up in the clutch hub.

I'm thinking of just going to the stock setup but dont have any of the original parts.

Any have any experience with the mikes clutch bolt setup?

 

[kshansen]

Do you have the pressure plate indexed correctly with the hub?

That black dot at 12 O'clock in the above picture is a shallow hole drilled in the edge of the hub.

What looks like a black mark at 12 o'clock in this picture is actually a hole drilled right through the pressure plate. This hole has to be aligned with the mark in the above picture of the hub for clutch to work.

 

[lidirtrider]

I will double check that. One thing i did find though, was one of the aluminum sleeves was crushed and mashed into the spring, not allowing the spring to, well, spring. So that may have been at least part of the issue.

 

[kshansen]

I will double check that. One thing i did find though, was one of the aluminum sleeves was crushed and mashed into the spring, not allowing the spring to, well, spring. So that may have been at least part of the issue.

Well if the aluminum sleeves or even one was causing a bind on the springs that would not be a good thing for sure. If you have the original steel spring retainer bolts and springs I would stick them in just for a quick check.

I have the transmission out of the original engine of my 1982 and planing on modifying the spring retainer, screws/bolts or what ever the correct term is, to take some kind of allen head bolts. Just need to decide on how I'm going to bore them out, most likely will chuck them in the lathe. Would like to find a collet the right size as that would make doing a batch of them easy, less set up time for each one!

 

[XSLeo]

Take one of your old steel clutch spring bolts to the hardware store. Find Allen head bolts the same size and thread pitch as the threaded end of old bolt. Get ones that from under the head to the end of bolt to the end as the old bolt is from on top of bolt head to end of the threaded end. I think about 45 mm long. Long enough so that when you complete the next step the threaded bolt protrudes as much as the threaded parts that falls off .
I have a 4 inch drill press vice. I drilled a 14 inch hole where the jaws meet. After I did this I hold the drill press down to hold the vise in place to clamp the vise to the drill press plate. I then raise the drill. Take the drill bit out of the drill press, put it in the vise. I then put one of the old steel clutch spring bolts into the drill press, threaded part up in the chuck. Now the drill press turns the old bolt, the vise holds the bit. Always centered this way. Drill into and through the old bolt.
When the bit gets far enough through the old bolt, the threaded part falls off. Repeat with all five more old bolts.
Know with the clutch hub and new bolts assemble the new bolts into the hub. Check the back of the hub. With bolts tight you want the bolts to come no more than flush with the back of the hub. If longer they will cut into the clutch basket. If they do stand proud of the hub, grind them back flush.

Leo

 

[kshansen]

I have a 4 inch drill press vice. I drilled a 14 inch hole where the jaws meet. After I did this I hold the drill press down to hold the vise in place to clamp the vise to the drill press plate.

Dang Leo where did you find the 14 inch drill bit and how big is this drill press? Just kidding!

I took a look and see I have a drill chuck I can mount in the head stock of my old lathe and use that to hold the spring bolts. I then looked at the chart and see that a 6mm converts to 0.236 inch and a 15/16 drill bit is 0.234 inches so that should give me a nice fit on the allen head bolt.

A quick measure and I think a 40mm long bolt will do the trick and I'm leaning towards a button head bolt to keep the overall height down with out having to counter bore the original spring bolt. Check with McMaster Carr and found these:

Not sure what the shipping will be but for 25 I would end up with enough for 4 engines. Might do a couple test drills in the next few days then double check the length of bolt I need and order some up.

I'll try to post back here with some pictures of the final product.

 

[lidirtrider]

Took the pressure plate off and sure enough, I did not have it indexed to the correct position. Still gotta get new bolts and sleeves, and prob springs too, but that seemed to be the issue.

 

[TwoManyXS1Bs]

...Check with McMaster Carr and found these:

View attachment 99593

You may not like the 4mm drive size.
Available with 5mm drive?

 

[kshansen]

You may not like the 4mm drive size.
Available with 5mm drive?

Or might just go with simple hex head cap-screws.

 

[lidirtrider]

Alright so I discovered that I had things assembled totally wrong. I found all the washers, and some some great diagrams here on the board. Reassembled everything, and as soon as I put the plates and pressure plate on, I cannot crank the kick lever at all. Pull the clutch, and inner hub rotates smooth as butter, Let the clutch lever out, and complete lockup. So, I'm thinking maybe a timing issue now?

With bike in gear, rotate kick lever, rear wheel turns.
Manually turn crankshaft with a wrench, clutch basket rotates, and timing advance weights rotate
Clutch lever pulled in, rotate kick lever, inner clutch hub and steel plate rotate easily.
Spark plugs in, rotate crankshaft manually, air sucks in, and blows out of carbs and exhaust.

So based on that, timing out 180 degrees?

The thing that gets me is even without the spark plugs installed, its like everything is just completely bound up. I measured all of the washers, and it appears I have all the correct sizes, according to info found here. Installed as per numerous diagrams on here, and still, not able to turn kick lever, even with all my weight on the lever.

 

[5twins]

kshanson, regular Allens fit just fine and are preferred because of the 5mm drive size, as mentioned. 40mm is the length you want. Grind the domed top flat on the original screws and that will add another 1 to 2mm to the screw length, making it perfect .....

https://www.mcmaster.com/#91290a336/=17nzrkb

 

[lidirtrider]

Next time I'll be able to get in the garage is friday, so I'll take some pics and video, and put it up here. Maybe that will help with the diagnosis.

 

[lidirtrider]

I finally figured out what my issue was/is. It wasn't the clutch at all..well sorta, it was assembled in the wrong order, but it is actually the PMA rotor rubbing one of the bolts and the stator plate. You can see in the first picture the wear marks on the lower right just to the right of where the wire comes through the plate. In the second picture is the uppermost bolt on the stator plate. It is the only bolt like that. The other ones all have about 2mm clearance ( measured with my mEYEcrometer). Any thoughts? I'm going to email hugh too.

 

[kshansen]

kshanson, regular Allens fit just fine and are preferred because of the 5mm drive size, as mentioned. 40mm is the length you want. Grind the domed top flat on the original screws and that will add another 1 to 2mm to the screw length, making it perfect .....

https://www.mcmaster.com/#91290a336/=17nzrkb

Sounds good, I was a little concerned about clearance to the side-cover. I'm doing this work in the lathe so facing them off nice and flat is no problem. Also going with regular allen head screws will make it even easier to source them. My other thought is/was to use hex head capscrews if the height of them is equal to or even less than the allens.

 

[kshansen]

The other ones all have about 2mm clearance ( measured with my mEYEcrometer). Any thoughts? I'm going to email hugh too.

With out seeing it in person it is a bit tricky to say, but is there a chance you could shave a bit of the inner edge of the rotor? Best bet would be to mount in a lathe to do it. Other idea would be to grind a bit off the head of the offending bolt and the contact point on the housing. The rotor I'm assuming is mounted on a taper on the crank so no easy way to "shim" that. If the taper in the rotor was machined by Hugh it is possible he got it a slight bit too big letting it go in just a touch too far.

 

[lidirtrider]

With out seeing it in person it is a bit tricky to say, but is there a chance you could shave a bit of the inner edge of the rotor? Best bet would be to mount in a lathe to do it. Other idea would be to grind a bit off the head of the offending bolt and the contact point on the housing. The rotor I'm assuming is mounted on a taper on the crank so no easy way to "shim" that. If the taper in the rotor was machined by Hugh it is possible he got it a slight bit too big letting it go in just a touch too far.

Yeah I thought of grinding the head of the bolt down, or using button head allens, and also taking a bit off of the stator bracket to make everyting clears a little more. My concern is that there is an underlying problem that the rotor seats too deeply or is not sitting paralel

I dont think hugh produces the rotors, just sources them in his kit, but manufacturing could be an issue. I dont have a lathe so I wouldnt be able to turn down the rotor, and even if i could, something about changing the specs of a heavy rotating part doesnt seem too appealing to me.

My first step, besides emailing Hugh, is to just pull it all off and start over and make sure there was no error in the install and that all the parts are flat and true.

 

[retiredgentleman]

You have bought Chinese parts and its common that the parts don't fit properly.

 

[ebb0tk]

Borrowing thread a bit rather than starting a new one.

My dilemma is: Ive done the allen mod to bolts. I have the later style clutch with longer springs. I have spacers to equal length of new springs (for early clutch and are stiffer) but 40mm allen heads are not enough. Another thread said 45mm will rub at the back side. So can i ditch the spacers? Or do i need 45mm for my setup?

 

[5twins]

The length of the screw used determines how much will stick through the spacer and out the back of the hub. 45mm long screws are too much, they stick out too much. I replaced the pics in post #11 above. Look at them and you'll see 45mm screws won't work.

I don't think the 40s you have are too short. You'll just have to push in on the screws to compress the spring a little to get them started in the holes. Your added spacers look pretty thick, maybe too thick. The springs may get coil bound once you tighten the screws down fully. That would lock the pressure plate in place and not allow it to move when you pull the clutch lever. In fact, you wouldn't be able to pull the clutch lever in. It would be locked too.

 

[ebb0tk]

Yeah i did the spacers so i would get the same height as old springs. Guess i miss calculated that.

Should i turn the spacers down in the lathe until the 40mm screw sit flush like the last picture you attached?

Are do you have anything else i should consider?

If i remember correctly i have 6 friction plates. its a 1981 -europe model