Kawasaki VN750 Forum banner

1 - 20 of 39 Posts

·
Registered
Joined
·
25 Posts
Discussion Starter #1 (Edited)
Howto: ACCT to MCCT using Set Screw

How to Create an MCCT using a Set Screw

There are two good DIY ways to convert the ACCT to MCCT. Both methods cost less than a cocktail.

Way #1. Buy a new hex cap screw, nuts, and washers. Throw away the old rod, bushing, spring, and internal washer. Use the new bolt instead of the old rod, replacing a moving assembly with a fixed bolt adjusted to tension. Cost: about $6/ea. Info here.

Way #2. Install a set screw in the housing to hold the rod in place. The pressure of the set screw is applied directly on the rod and held by friction. Throw away the old spring. Cost: about $1/ea, or $10 total if you need to buy a tap too.

Both methods cheat the original design. They rely on the strength of the housing, which may be a fatal flaw. Way #1 seems safer in that regard; Way #2 is probably catastrophic to your engine if anything comes loose while you're riding (i.e., the cam chain will lose all tension and potentially tear up the cam).

I chose way #2, here's why...

Pros:
* Fewer parts to swap out & match, lower cost
* Looks better. Uses original cap screw. The only visible difference is a cool looking set screw in the CCT housing
* No messing with washers or leaking oil, new washers/rings, etc.
* Seems easy to adjust from the road

Cons:
* Requires permanent modification (drilling and tapping housing)
* Housing strength is unknown. Set screw could strip out, leading to engine damage.

Ok, so here we go!

Photo album here.

Parts Required

#10-24 x 1/2" Cap Screws (2)


Optional, if you don't have the right tap already:
#10-24 tap + #25 drill bit combo


Step 1 - Remove ACCT assembly

As others have said, you will need to bend a metal tab connected to the oil line. I accomplished this with needle nose pliers.





Step 2 - Disassemble

Notice that the spring is set aside. You will need all the other parts.

At this point you may be wondering what the set screw will hold in place. The smooth part of that long internal rod will be in direct contact with the end of the set screw when we're done.



Step 3 - Drill and Tap

First, drill a hole in the housing. Something in the middle will work. After drilling, use the tap to thread the hole. I used a lock wrench for my tap.



Your set screw will now screw in and out with no resistance.



If I were to do mine again, I'd go a little more on top because I had trouble getting my socket on the acorn nut without removing the set screw on installation.

Step 4 - Install and Caliberate

You'll need a screwdriver that can fit that rod in the assembly.



a. Re-install the whole thing, keeping the set screw loose. Don't worry about that oil line tab.

b. Go get an allen wrench. Tighten the set screw down against the tension rod until hand tight, then get your allen wrench in place. You're going to need it to tighten down the tension rod after getting it in place.

c. Adjust the tension rod to about half way. Expect to hear clacking when you fire the bike up.

d. Fire up the bike.

e. Use the screwdriver to adjust until clacking goes away. Being that this is my first time, I had to tighten it down much farther than I imagined before the clacking stopped. Don't be afraid to tighten "through" the clacking, and you'll hear it go away. You have to hold this in place, and you'll feel it in your screwdriver hand even though you can no longer hear a "clack".

f. When you find a point where the clacking stops, keep holding the screwdriver in place. Use your free hand and allen wrench to tighten the set screw. When the set screw snugs up against the rod and is tight enough, you won't feel the chain pushing against your screwdriver hand anymore.

Voila!

Step 5 - Your Story

Come back here and tell us your story with a final pic :)

I want to give a huge THANK YOU to everyone who helped and came before me. I feel like I have a new bike.

And credit for the inspiration.

 

·
romeobravo172
Joined
·
842 Posts
To me that sure looks better than a bolt and nut hanging out there, plus on the rear you should not have to move or modify coolant bottle--- Very Cool and looks easy enought to do! Thanks
 

·
Prowling Tiger
Joined
·
2,048 Posts
To me that sure looks better than a bolt and nut hanging out there, plus on the rear you should not have to move or modify coolant bottle--- Very Cool and looks easy enought to do! Thanks
Actually, i think the coolant rez will need to be moved since the head of the acct hides behind it and the internals will need to be removed.
 

·
Registered
Joined
·
25 Posts
Discussion Starter #6
Actually, i think the coolant rez will need to be moved since the head of the acct hides behind it and the internals will need to be removed.
He was referring to an earlier thread where someone mentioned having to modify the shape and placement of the reservoir because the new CCT bolt stuck out further.

The solution presented here doesn't require any modification to the coolant reservoir but yes you do need to remove it to get at the back CCT.
 

·
Member? ... check.
Joined
·
515 Posts
This is a simple method, but I have to say, this mod still relies on soft metal for a torque retained assembly. I know set screws used in this method work well with hard metals such as stainless where thread torque can be quite high, but my experience with machines would never allow me to completely trust this solution. I think the TOC's design offers the greatest insurance for the buck.

My2cents.

disclaimer: I am not a mechanical engineer or machinist.

~~C8>
 

·
Registered
Joined
·
245 Posts
Looks neat but what is there to stop the bolt vibrating loose, if it does your engine is toast??
You could drill a small hole in the head of the SHCS, and wire it to the body of the ACCT.
 

·
Prowling Tiger
Joined
·
2,048 Posts
You could drill a small hole in the head of the SHCS, and wire it to the body of the ACCT.
Why not use a nut to tighten against the housing of the ACCT? Or, maybe, some sort of thread lock? I like the concept, but I have the same concern as the other poster about the integrity of the ACCT housing. If the housing is aluminum or some other lower grade steel than the screw, that screw will tear it up; then you are left trying to find a replacement housing and a bike that sits until fixed.
 

·
Registered
Joined
·
25 Posts
Discussion Starter #12
Why not use a nut to tighten against the housing of the ACCT? Or, maybe, some sort of thread lock? I like the concept, but I have the same concern as the other poster about the integrity of the ACCT housing. If the housing is aluminum or some other lower grade steel than the screw, that screw will tear it up; then you are left trying to find a replacement housing and a bike that sits until fixed.
I agree with these concerns.

The drilling and tapping did seem like soft metal because it went relatively easily. The thought crossed my mind at that point.

So far I've driven about 30 miles with no issues. tI'm going to ride it for a few hundred miles this weekend, then I'll report back.

The other approach does seem safer overall. The likely worst case for Way #1 is that the nut loosens and you stop to tighten it again. The likely worst case for Way #2 is that your housing fails...

On the other hand, I didn't have to tighten the set screw down that forcefully. But in general I still agree, perhaps the approach is too risky for the benefit.

My plan was to try this out and then just order the TOC MCCT if it didn't work out :)
 

·
Registered
Joined
·
3,353 Posts
I like that you tried to think of a different way to approach this, but I too have concerns about the risks in the event of a failure. I give you credit for taking a shot at a "better way".

I think that unless the shaft is dimpled, the set screw could slip. It is also possible that the thin wall and soft metal of the housing will let loose of the set screw.

The other method seems more secure, but I didn't want to trust the thin material of the threaded housing on that either. I eventually found a set of the TOC MCCT and installed them.

I still have my original ACCT's and will be looking at those a bit and see if there is a different approach that might work.
 

·
Registered
Joined
·
619 Posts
Don't get me wrong I read these posts eagerly hoping that they work and do the job because unfortunately over here we simply do not have the spares or back ups that you guys have in your country,so if it works long term and is easy to do then I am all for it, :smiley_th
 

·
Registered
Joined
·
25 Posts
Discussion Starter #15
The other method seems more secure, but I didn't want to trust the thin material of the threaded housing on that either.
I think that sums it up pretty well. Both methods rely on tension against the housing when the original design was not. The one from TOC is designed for it.

Given that, it is probably worth the $100 to have a new MCCT assemblies from TOC.
 

·
Registered
Joined
·
25 Posts
Discussion Starter #17
Why not use a nut to tighten against the housing of the ACCT? Or, maybe, some sort of thread lock? I like the concept, but I have the same concern as the other poster about the integrity of the ACCT housing. If the housing is aluminum or some other lower grade steel than the screw, that screw will tear it up; then you are left trying to find a replacement housing and a bike that sits until fixed.
Maybe thread lock.

I think a nut would create more pressure on the housing threads. Tightening the nut is effectively pulling the bolt tighter against the threads (to stop it from loosening).

Right now I can't think of any solution that uses the housing as originally intended. TOC's MCCT seems best.
 

·
Registered
Joined
·
619 Posts
Yeah if you could put some kinda steel threaded sleeve in the ally part it would give it strength, I have used something before that you put an insert in with a tool of somekind but it was years ago and memory not what it was :smiley_th
 

·
Registered
Joined
·
3,353 Posts
I was planning on taking apart my now unused ACCT and looking into a "filler" on the inside of it so it could be drilled and re-tapped with a stronger inner wall.
I was thinking of filling it with aluminum brazing rods and then drill and tap it.
 
1 - 20 of 39 Posts
Top