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Author Topic: Hondamatic 750 Camshaft  (Read 3325 times)

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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #25 on: July 08, 2020, 07:45:27 PM »
And yes, I'm doing this on the back porch at my apartment lol. Don't judge me. I already get plenty of that from my wife.
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Offline Alan F.

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Re: Hondamatic 750 Camshaft
« Reply #26 on: July 08, 2020, 08:17:44 PM »
No judgement, I put a bike together on the back porch this spring before I picked up my K8. The K8 is going together in an unpaved parking space behind my apartment. My basement workshop is only good for so much. (Stairs suck)
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #27 on: July 09, 2020, 08:22:59 AM »
We're looking to buy our first house in the next few years,  and a work shop is definitely in the picture. This old CB has played a major role in keeping me sane in the past couple months of unemployment. So there's definitely going to be other projects after this. Ive found I really enjoy bringing these old bikes back from the dead, My first bike was a 78 Yamaha 650 Special, and I've been thinking about tracking one down to do after I'm completely finished with the CB.
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #28 on: July 11, 2020, 11:27:54 AM »
Failure, it's together and it runs. But theres a bit of valve chatter. The Jug gasket is leaking pretty good right under the timing chain tensioner, do you guys think that is causing the chatter, Cause insufficient oil flow to the head? I set the valve tapits at 0.05 intake, and 0.08 exhaust. I suppose I could have botched that...I understand you guys are speculating, and you can't give me a very accurate answer because your not here with me. But any theroy's are welcome.
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Offline bryanj

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Re: Hondamatic 750 Camshaft
« Reply #29 on: July 11, 2020, 11:43:56 AM »
If that is thou the gap is too big, did you not change the base gasket?
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #30 on: July 11, 2020, 11:46:32 AM »
Yeah, I did. I got an entire gasket kit. And I sealed it too. Not sure what went wrong.
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Hondamatic 750 Camshaft
« Reply #31 on: July 11, 2020, 11:53:36 AM »
Quote from: JerrodR on July 11, 2020, 11:46:32 AM
Yeah, I did. I got an entire gasket kit. And I sealed it too. Not sure what went wrong.

Sealed it??!! Surely you didn't put a sealer on any of the gaskets?!
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #32 on: July 11, 2020, 11:56:47 AM »
Not the gasket, on the crank case before I placed the gasket down.
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #33 on: July 11, 2020, 11:57:51 AM »
That's what Gasket sealer is for isent it?
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Hondamatic 750 Camshaft
« Reply #34 on: July 11, 2020, 12:14:14 PM »
Do NOT use GASKET sealer on these bikes. They go on dry. Gasket sealer will/can break loose and plug up the cam tower oil jets!!!!!! DO use a sealer between the case halves. I use Threebond 1104 on the case halves. Honda and Yamaha make a sealer that many use but just on the case halves. Oh, also I use it to seal the pucks under the cam towers.

I hope you have now determined there is ample oil flow to the cam towers as viewed through the tappet adjuster caps on 1 and 4.   
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Offline ekpent

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Re: Hondamatic 750 Camshaft
« Reply #35 on: July 11, 2020, 01:02:14 PM »
Quote from: bryanj on July 11, 2020, 11:43:56 AM
If that is thou the gap is too big, did you not change the base gasket?
As Bryan stated if thou then it should be 2 on intake and 3 on exhaust. 5 and 8 happens to work on a Suzuki 1200 Bandit  ;)
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #36 on: July 11, 2020, 02:20:20 PM »
I set the valve clearance's from the Clymer's service manual, but at this point I don't think that's my problem. It's running better then before, it's not getting through an entire revolution and it's fireing and running. There's just an unhealthy amount of valve chatter. It's not getting sufficient oil to the top end, and I'm leaning towards the gasket sealer being the culprit. It make perfect sense..
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #37 on: July 11, 2020, 06:43:47 PM »
Ok, flow to the rocker towers us fine. I'm readjusting my valves to 0.02 and 0.03 right now, and we'll see how it go's.
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Offline Alan F.

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Re: Hondamatic 750 Camshaft
« Reply #38 on: July 11, 2020, 07:23:51 PM »
Cam chain tension?
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #39 on: July 11, 2020, 08:30:33 PM »
Nope, my manual gave me the wrong valve clearance tolerance's. I set the exhaust valves at 0.03 and it hushed them right up. The intake valves are at 0.05 so they weren't that bad, but I'm gonna pull the header and drop the front of the motor tomorrow so I can get to them. That Hondamatic Cam did not cut the power at all.. Its gotta lot more low end guts now. Feels real good. I didn't wanna get off, but I gotta park it till I can get those intake valves in spec.
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #40 on: July 11, 2020, 08:44:12 PM »
Thanks for the help guys. This forum is cool, it's just me my wife and my little boy, and they don't know much about what I'm doing lol, it's cool to be able to contact people with my experience then me.
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Offline PeWe

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Re: Hondamatic 750 Camshaft
« Reply #41 on: July 11, 2020, 10:01:06 PM »
Good idea to have in mind when assemble that it should be easy to take it apart again .
Sealer on gaskets is not needed and is pita to take apart next time. Gasket will probably be destroyed. All engine cover gaskets can be reused if taking cover off.
Honda and  Yamiya use good quality that fits very well too.

To set a side cover in place when assembly, "glue" it wirh oil where needed.

I did a mistake once to use copper spray on an fiber head gasket it leaked a lot direct, despite high torqued.  Just to redo it.

Just to redo and enjoy the bike!
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #42 on: July 11, 2020, 10:14:38 PM »
That's the plan, just a bit more work and I'll be in the wind again. It's supposed to rain here in Ohio tomorrow anyways.
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Offline scottly

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Re: Hondamatic 750 Camshaft
« Reply #43 on: July 11, 2020, 10:26:17 PM »
Quote from: JerrodR on July 11, 2020, 08:30:33 PM
The intake valves are at 0.05 so they weren't that bad, but I'm gonna pull the header and drop the front of the motor tomorrow so I can get to them.
You don't need to do all that to check/adjust the intake valves, you just remove the tappet covers. What about the oil leak under the cam chain tensioner?
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Offline ekpent

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Re: Hondamatic 750 Camshaft
« Reply #44 on: July 12, 2020, 04:12:44 AM »
 The cam chain tensioner also has its own gasket. Not sure if it was removed while you were working on it.. Seems the last gasket kit I bought did not have one of those and I had to make my own.
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #45 on: July 12, 2020, 06:28:22 PM »
No, tentioner never came off, and yes I discovered those when I was getting ready to start taking out the mount bolts. Saved alot of time. And as far as the leak is concerned, I'm not sure. It just stopped while I was working on getting the valves sorted. I was thinking maybe pressure moved the gasket into position, I'm not sure. But I was out for 4 hours with my Cousin today and it didn't leak a drop.
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Offline JerrodR

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Re: Hondamatic 750 Camshaft
« Reply #46 on: July 12, 2020, 06:35:33 PM »
My Cousin was saying sometimes things need to settle into place after major work like that. But it ran great today, kept it under 4 grand for the first 200 miles, and then turned it loose a little. I think the extra time I took getting the timing sprocket and the Cam lined up the best I could payed off. Ran smoother then before, and felt stronger then when I bought it.
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