HarleyTechTalk

It started out as a regular oil change and as the main hole was filling the primary was draining.



Inspection of the dirty but still red ATF that came out of the primary revealed some small balls of metal,        so off came the primary cover.   All looked normal but there were metal flecks visible everywhere, further dismantling was required.

The first thing to come out was the Southern Oregon Hot Bikes HB125 Hydraulic Primary Chain Tensioner which I'd put in years ago after having tried the ill fated HD Automatic Tensioner.   After taking it out it was obvious where the metal had come from, the bottom of the tensioner had busted out.  What started out as one or two pieces breaking away was turned into round balls and lots of flecks by the chain and sprockets.

A file pic, but I'll take some of the damage in the morning.



So the rest of the primary components needed to come out to ensure all the pieces of metal were removed.

A locking bar, comp to clutch basket and an old clutch fibre riveted to an old steel will lock the clutch up so that the clutch nut and comp nut can be removed.



The fibre/steel is only at the outside edge of the basket for the pic, attempting to undo the nut with it in this position runs the risk of damaging the basket,



it was pushed to the back of the basket when undoing the nut




It's Friday night football, so more tomorrow.   

If you will get in touch with Hot Bikes of Oregon, they will send you a new one for free. They had a bad run a few years back which caused the c-clip to blow off releasing the ball bearing and spring. I had one do the same way two years ago. It took a while for it to show up but they will stand good for it!

Quote from: FSG on May 16, 2014, 05:46:17 AM

I see you're too fancy for a regular old funnel. . .

Quote from: mattVA on May 16, 2014, 07:54:05 AM

Quote from: FSG on May 16, 2014, 05:46:17 AM

I see you're too fancy for a regular old funnel. . .

Naa. It's just good to the last drop!

Quote from: FSG on May 16, 2014, 05:46:17 AM
It started out as a regular oil change and as the main hole was filling the primary was draining.

HEY!  FSG is a multi tasker ya know!!     

We'll that's a bummer finding metal pieces in there. But good you found it too.

Thought this thread was going to go the other way. You know, went to change oil and accidentally put a high performance top end in there. Then built the lower end with it, just 'cuz.

"We'll that's a bummer finding metal pieces in there. But good you found it too."

Hope all inside the primary is OK. Going back to stock adjuster?

I love that clutch hub locking tool.   Bet it was conceived while sitting over near that well stocked bar in the background...

Quote from: rageglide on May 16, 2014, 04:47:07 PM
I love that clutch hub locking tool.   Bet it was conceived while sitting over near that well stocked bar in the background...

        wasn't far from it 

Pix of the blown out HB125   







I'll send the pix and my info to Hot Bikes of Oregon to see what they may do, but I'll want this bike back on the road within 3 or 4 days, so the stock adjuster will go back in.


Some chain touchdown marks.

QuoteI see you're too fancy for a regular old funnel. . .

    It's not really a funnel, just an old seismic cable fitting I have laying around that is the right size for the tank and a snug fit for the oil bottle.   I pour the contents then let it drain while I'm off doing something else.    Ohio HD   

OK while I'm at this point I've measured things up and am making a FSG Sprocket Shaft Spacer.  It will encompass the spacer that sits between the rotor and the sprocket shaft extension (depending on sprocket alignment) which will move the rotor outboard by the thickness of the spacer, in the case of my Fatty it's .130" wider  and will be larger in diameter where the rotor butts up against it (55mm) for approximately 12mm on the outboard side of where the seal runs.

Material at this time is T11.   Pix and dims when I get it on Monday afternoon.

Movement of the rotor outboard by .130" will do SFA to the operation on the charging system.

The increase in the outer diameter of this FSG Spacer will provide around 3.2 sq" of clamping area up from the meager 0.88 sq" of the stock spacer.

Damn you got lucky catching it when you did. Mine blew the clip off and the ball bearing went around in the primary. It would lodge every now and then between the clutch basket and the primary case. Got to Sturgis later that day and tore it down to find the problem. Put a stock one back in that I carried with me for a spare and was on the road again. Cleaned everything up really good and haven't had any problem since.

Good catch, fsg. Wonder how many shops would've even looked in the drained oil?
Nice use of the seismic coupling.   

OK here it is, I made a mistake earlier when I said T11, it's actually H11 tool steel.

I lube'd it up an trial fitted it before taking the pix.  In this pic you can see where the seal runs.












Now that's something descent for the rotor to press against.








I ran a 3/8" Tap through the two holes while the rotor was out.  While not really necessary it does make rotor removal/installation a lot easier.

As said earlier the material is H11 Tool Steel

Dims are mm with inches in brackets.        I may me a few thou short on the overall length but it'll not let it worry me.   

That looks good. Do you have a patent pending?

Quote from: FSG on May 16, 2014, 10:03:35 PM

Quote from: rageglide on May 16, 2014, 04:47:07 PM
I love that clutch hub locking tool.   Bet it was conceived while sitting over near that well stocked bar in the background...

        wasn't far from it 

Pix of the blown out HB125   







I'll send the pix and my info to Hot Bikes of Oregon to see what they may do, but I'll want this bike back on the road within 3 or 4 days, so the stock adjuster will go back in.

It sure looks like the snap ring was installed backwards.  The rounded edge should be in back and the crisp sharp edges should be showing.  That said all the loading was on the inner edge of the aluminum and that is why it failed. If the loading were back against the base of the cut it would have lots more strength.

QuoteIt sure looks like the snap ring was installed backwards. 

  that it was.

QuoteThe rounded edge should be in back and the crisp sharp edges should be showing.

  yep

QuoteThat said all the loading was on the inner edge of the aluminum and that is why it failed.

  yep

QuoteIf the loading were back against the base of the cut it would have lots more strength.

  yep

and I'll add that the gap in the snap ring should have been facing the other way.  I could say more now that I have this thing in pieces but will refrain, I sent these pix to the makers and they asked for my address so perhaps they are going to send me a replacement.

For now this primary will be going back together with the stock tensioner.  Pix later of a Baker 27T Sprocket and chain may also dictate that a stock tensioner be used.

This is not a realistic situation but shows how far the sprocket could rotate if there were no springs in the cover and the sliding cam was able to travel until it hit the back of the cover, which I measure to be 8.5mm. 

3.5mm gap between the springs



the gap between the end of the shaft extension and the inside of the cover (hard to measure) is approximately 2mm, so once the comp nut has been torqued to spec the gap between the springs will be down to 2.5mm so the sliding cam will only be able to travel 5mm (3.5 + 3.5 - 2 = 5).



My thoughts are to put another spring (in parallel) into this cover spring pack, BUT the springs are 2.3mm thick so adding another and torquing the comp nut to spec the gap between the springs will be reduced yet again, down to 1.35mm so the sliding cam will only be able to travel 5mm (3.5 + 3.5 - 2 - 2.3 = 2.7).   
This will not be a sensible option as the springs will be flattened and the sliding cam bottomed out  too early in the engine power pulse.   

To fit an extra spring in parallel the cover spring pack needs to be spaced away from the shaft extension by the thickness of a spring.   Actually with the spacer I'll be leaving out as I've incorporated it into the new sprocket shaft spacer will be ideal for this.





This will have the comp nut further to the left so the question is how far left can it go before it hits the inside of the primary cover. 

The nut face is 55mm to the left of the inner primary edge



The primary cover is 62mm deep to the ribbing in the  comp nut area.   

Here's a 27T Comp Sprocket and an 84 Pitch Chain, no way the Stock Chain Adjuster is going to cope with that.  I'll be needing a 2000 or earlier Chain Tensioner, complete, so that I can flip it for adjustment.



what I'm going to need.






Stock 25T and 82 Pitch Chain fits like stock       Note: sprocket shaft off cut providing support.



5 Spring pack to go on

Putting it back together the 2 pop rivets in my fibre/steel clutch basket locking tool sheared, so I put a few more rivets in it.

This is how the sprocket shaft spacer and compensator with extra spring is going back in.

awesome explanation and pics bro!

A couple of studs or all thread will have the primary gasket hanging in there, put the primary on and secure a few bolts then remove the studs/all thread.



That's the original OEM gasket that came on this '03, I've lost count how many times the primary has been opened.



New fibre washers are required, something to get in the morning.

FSG, I'd be interested in hearing about any differences that you notice between the HB-125 and the stock chain tensioner in normal riding conditions.
I specifically checked my HB tensioner from following this thread and mine looks like it should.  I've thought about going back to the oem tensioner though...