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Discussion Starter #1
That happened a few hours ago while my bike was on the dyno getting tuned.

Not sure what happened as I torqued that bolt according to spec and it backed out along with the cam which pushed into the head and started digging.

When I rebuild it I'm thinking thread lock next time to avoid this situation.

Anybody else had this happen?
 

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I have heard of it happening when no threadlocker was used, I think @CiscoSanJose had that issue but I can't remember for sure.
 
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Discussion Starter #5
Going to update this thread and my other thread.

Just pulled the cam out and saw it has wear on one of the lobes and also the cam cover, retainer plate and bolt have wear.

So the head will have some wear in the rocker chamber from cam contact but otherwise there is very little abuse that happened. Cam sprocket has barely noticeable wear.

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At least parts are cheap for these bikes, you can have it running again soon if you want to hold off on the bbk.
 
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Isopropyl Alcohol. I am lucky that my job lets me access as much IPA and lint free swabs as I like. It comes in handy, especially for detailing.

I also like to use this cheap little telescopic magnet from Harbor Freight, I'll sometimes fish it around to pick up fragments from crevices. Would have made fishing out needle bearing rollers from my engine easier when m head exploded.

I should clarify, you want as close to pure 100% IPA as you can get, I believe you can get 99% off Amazon. Lower % (70% is common) contain water.

Ensuring you have close to pure isopropanol means you can put it in a spray bottle and hose it, if its a small part, or use on cloth to wipe - while ensuring it evaporates without leaving any residual water.
I had a similiar experience when my Koso cam chain tensioner failed, the above is good advice that I followed. I am over 2000 miles since the failure.
 
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That and change the oil VERY FREQUENTLY until you stop seeing silver specs in it.
 
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Discussion Starter #11 (Edited)
Not a contest I wanna win, but I think my failure was worse! Lol
Glad it wasn't as bad as that. I could just get a replacement cam, the cam plate and bolt and a flush and be good, for a little while.

The fact that the chain was grinding on the cam cover is enough motivation to tear down and get a new chain in there which I have with the new crank.
 

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Discussion Starter #12
I'm still pissed that this piece came out/apart.

When I was torquing it down I was thinking how unsecure the plate felt.

I'm not sure of the arrangement of the new setup on the Takegawa 4 valve but my understanding is there is a groove and lock ring that holds it together so long as that is installed correctly there should not be any problems.
 

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I don’t think I used Loctite on the retainer plate. Can’t remember. Fingers crossed that it never comes loose. I do use a torque wrench for everything though. The bolt for the cam sprocket, I cleaned the threads first with rubbing alcohol on a Q-Tip, then used Blue Loctite.
 
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He is not the first to have that problem, might be worth checking one day while you are adjusting the valves.
 
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Discussion Starter #15
I don’t think I used Loctite on the retainer plate. Can’t remember. Fingers crossed that it never comes loose. I do use a torque wrench for everything though. The bolt for the cam sprocket, I cleaned the threads first with rubbing alcohol on a Q-Tip, then used Blue Loctite.
This is now the 4th time I've had the cam out and always following the book regarding the oil on the threads and the torque value.

I remember getting a weird feeling about the bolt and plate too as I was reassembling but wasn't sure about deviating from the manual and putting some loctite on it.

I've got a Kitaco Type 2 on the way and new bolt and plate. Loctite for sure this time around. No chances for failure.

I torqued the cam sprocket per manual as well(everything for that matter) and it was still tight but that is a higher number no doubt because it is steel bolt into steel cam unlike the cam retainer bolt into the aluminum head.
 

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What page in the Monkey manual does it say to oil the threads and a torque value? All I can see on page 9-8 is “ install and tighten bolt”.

The Takegawa instructions show the torque value as 12nm but nothing about oiling the threads either
 

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Discussion Starter #17
What page in the Monkey manual does it say to oil the threads and a torque value? All I can see on page 9-8 is “ install and tighten bolt”.

The Takegawa instructions show the torque value as 12nm but nothing about oiling the threads either
I can't find where I found it now.
 

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He is not the first to have that problem, might be worth checking one day while you are adjusting the valves.
Yeah, I should check it sometime. I absolutely hate removing that OTB Prototypes clear cam cover though. It fits waaaaay to tight. I finally figured out a way to remove it without damaging it last time. Next time I’m in there, I will definitely add Loctite.
I remember getting a weird feeling about the bolt and plate too as I was reassembling but wasn't sure about deviating from the manual and putting some loctite on it.
I wasn’t sure about deviating from Honda’s recommendation either, but had read of a few instances where the cam bolt came loose and all hell broke loose.
What page in the Monkey manual does it say to oil the threads and a torque value? All I can see on page 9-8 is “ install and tighten bolt”.

The Takegawa instructions show the torque value as 12nm but nothing about oiling the threads either
I’ve never looked in the Monkey manual, but I’m pretty sure it says it in the Grom manual. It must, because I remember knowing that I was supposed to put oil on it. I cleaned the threads real good with rubbing alcohol to make sure the Loctite bonded really well. I think some types of Loctite are oil resistant, though. Bolts with Blue Loctite are usually pretty reasonable to remove, unlike red Loctite, so I wasn’t too worried about it.

I’ve got a friend that literally Loctites pretty much everything on his motorcycles. He loses so many bolts on his off-road bikes. All his bikes end up with mismatched bolts because some of them fall out and he replaces them with a generic bolt from some motorcycle bolt kit.
 
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...

I’ve got a friend that literally Loctites pretty much everything on his motorcycles. He loses so many bolts on his off-road bikes. All his bikes end up with mismatched bolts because some of them fall out and he replaces them with a generic bolt from some motorcycle bolt kit.
Loctite on any bolt that is essentially a Jesus bolt. Jesus nut - Wikipedia

"single point of failure which results in catastrophic consequences. "

Brake caliper bolts are usually in pairs so they can be greased. Axle bolts that don't have pins to prevent them coming off would benefit from locktite.

That cam bolt is a "jesus" bolt.
 

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Discussion Starter #20
I checked my Monkey manual and sure enough it just says tighten. Very un-Honda-like.

I've also got Takegawa instructions plus the many videos/forums researched online. Had not seen the instances of it backing out though.

Certainly know better now.
 
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