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Discussion Starter #1
Had some leaks at the base gasket and head then found some other issues so off to the Machine Shop. The crankcase had the old gasket material removed with what appears to have been a Roloc disk or as some call whizzer wheel which left some low spots. The machinist took off .00075 off and has it looking sweet. After I received my valve removal tool I found the bronze exhaust valve guides (both) had a "rough" spot on (in) them around 3/8th" from the top. Not sure who did the bronze valve guide install. Machinist honed the tight spots and did a complete head job and "cleaned up" mating surfaces (not sure how much he took off, as of today). The cylinders are getting new .25 over size pistons, rings and all and the mating surfaces cleaned up as well.
My question is how will I know if clearances are okay? I've read about measuring squish and claying but I hope I'm just being paranoid and need to put the thing together with a Vesrah VG145 gasket set. Been thinking of using Cometic copper head and base gaskets also and could just get them a hair thicker I suppose.
Any thoughts on this are appreciated.

Thanks
 

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Discussion Starter #2
More details.

Pistons are coming from here. Scrambler Cycle - Home They are reproduction OEM. Not exactly sure what that will mean for reliability or performance but Bore-Tech didn't have what I need and no way I can afford Weisco from Charlie's Place.

Using stock cam.

KA slipper cam chain tensioner and heavy duty cam chain.

So. Is removing say .001" or so total of material from all the mating surfaces from the top of the crankcase to the head a concern? That would be a little from the base surface at the crankcase, some off the top of the jug and some off the head. Sorry I don't have exact number now but I'm trying to put my mind at ease as to whether or not I should be concerned.

Thanks.
 

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My understanding is "reproduction OEM" means parts that are remade by the original supplier to Honda. Same as if Keihn made new carbs from the original specs for our bikes.
 

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Discussion Starter #4
Cool. That makes feel a bit more comfortable about the parts going in. I'll be sure to speak with the machinist I'm working with to see if he has an opinion about them. Dude is on point so far and sort of geaks out on the whole process.

Sure hope someone chimes in on my concerns over clearance. I'd rather not do the whole trail and error thing on this one.
 

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Giving your machinist a copy of the FSM would give him the dimensions he would need. I hope he insisted on receiving the pistons before he bores the cylinders.
 

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.001" or .254mm should be fine to remove. Just have to check your cam timing, I think your cam timing will be slightly retarded. Piston and valve clearance should be fine, especially with stock cam.
 

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Discussion Starter #7
Thanks y'all.
Machinist has some copies from the FSM and yes, he'll have the pistons before he does the bore.

LiamG6. Is there anything other than the usual setting of valve clearance and ignition timing to lookout for if the cam timing is slightly retarded? I'm using the stock cam sprocket.

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The only thing that will need checking is the cam timing.
When you surface various arts the cam timing becomes retarded.
You may need to take a chain saw file and elongate the mounting holes slightly (way less than you would think)
I took 0.025" off head plus surfaced cylinder top
I forget exactly how much, (maybe 0.020"?) and it only needed about 0.035" on bolt holes to get timing correct
 

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Discussion Starter #9
Ah ha! So how to verify. I know that the line on the cam sprocket is supposed to be level with the cam housing and that the pin on the cam should be at 12 o'clock but all of that seems rather unscientific. Is that it?
Thanks crazyPJ! What's the X-ray of? Looks nasty.

Thanks again.
 

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My understanding is "reproduction OEM" means parts that are remade by the original supplier to Honda. Same as if Keihn made new carbs from the original specs for our bikes.
My understanding is Honda was the original manufacturer and they contract out reproduction parts they are no longer set up to make themselves. They are supposed to meet original standards, but........
 

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Ah ha! So how to verify. I know that the line on the cam sprocket is supposed to be level with the cam housing and that the pin on the cam should be at 12 o'clock but all of that seems rather unscientific. Is that it?
Thanks crazyPJ! What's the X-ray of? Looks nasty.

X-ray is the 'titanium race parts' in my lower back, fused L4, L5, S1.
At least I can stand for more than 20 minutes now though (as long as I keep taking the painkillers)
The 'correct' thing to do would be fit a degree wheel on crank but just lining up the points cam pin will work fine.
Use a straight edge between crank center to cam center
I removed all the rubber off cam sprocket then filed the holes, her's a pic

I did cut a couple of crescent shaped bits as I'm a bit paranoid about sprocket moving when just clamped with bolts, here it is fitted and timed

The actual offset isn't much and still looks 'wrong' but cam timing is now correct.
It isn't possible to get timing and line right
 

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Discussion Starter #12
Thanks Lefty. It's the but... I worry about. We will see.
 

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Discussion Starter #13
CrazyPJ, I feel ya on the back pain. I've got an L1 vertebrae that is squished 33%. Doesn't bother me too much though.
No worries about the "half moon" bits coming loose and going where they please?
The whole degree wheel and aligning stuff is sort of freaking me out. Only thing that comes to mind for a straight edge is a laser level but what the hell am I tying to line up? How do you have the end of the cam exposed on the points cam bearing side? Almost looks like one cut in half.
I'm sort of thinking of taking the easy way out and finding how much gets taken where and ordering Cometic copper gaskets that are thicker? Opinions on that idea?
 

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The pictures are CB360 bored to 378.
I didn't take many pics when I was doing 350's
All you need to do is have a line through centres of crank and cam, remove the advance mechanism.
The crescent pieces I made can't go anywhere unless the bolts come out first as they are under the bolt heads
 

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Discussion Starter #15
10-4. Sort of. Not exactly following the half moon idea but I'm sure you've got it dialed in. Thanks for the tips.
 

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Discussion Starter #16
CrazyPJ. Sorry about that last post. Brain was not engaged and I certainly meant no disrespect. I get it now. The "half moon" has no way of coming out unless the bolt does because the cam sprocket bolts to the cam. Duh.

The part about a straight line from crank to cam is still a little foggy. What is it I'm trying to accomplish? 12 o'clock for the pin?

Thanks again. I'll try to listen louder this time.
 

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your idea of slightly thicker gaskets is a known way to keep things right, without all the hassle of redoing cam timing etc. just go 0.125mm thicker on base and head gasket, maybe slightly more to factor in the compression of the gasket to end up at .25mm total after head is torqued down.

But if you do do it with slotted cam sprockets, your bike will perform better, as you can dial the cam timing in perfectly with a degree wheel and dial gauge (better than factory setting), and also you will get a minor compression bump which will help performance too. Not much though, so you decide, easy way with marginally thicker gaskets to restore stock height or get into some tuning.

if you just completely left it alone with stock gaskets and your timing is slightly retarded performance won't drop too much but won't be ideal.
 

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your way overthinking this...it's a stock motor with stock cam, stock type pistons...

the decking you are making are nominal. there is greater manufacturing variation between OEM HONDA cams than the small difference you are talking about.

gasket thickness differences between aftermarket and OEM will have a greater impact than decking your head.

copper gaskets are commonly thinner than OEM and will exaggerate timing change.

when i build 350 motors and need to deck the head I assemble them to check timing and on the rare occasion timing is too far off for my liking I'll add an extra cylinder base gasket.
 

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Discussion Starter #19
Thanks Outbie. I just came to the same conclusion. Guess I just needed the moral support. Maybe do a race bike someday and really dive into it.
As of now all Honda seals and circlips are ordered as well as a Vesrah VG145 gasket set. I plan on using 3m weather stripping adhesive on one side of the right side cover and the timing cover and a bit of grease on the other and leave everything else dry (unless I hear otherwise from the experts on here.)

I'll update his post when I get her going again.

By the way. Anyone notice iPhone autocorrect wants to put a capital p in piston? What like the the only time the word is used is for a dad-gum basketball team?
 

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Been there with the intense pain killers, PJ. Watch them. I got hooked on them years ago. Hard to break away from them. Now, just over the counter stuff and heating pad, and I wear a support from morning to night. I lost 1/3 of my bending ability after fusions (2) of T456789. 5678 exploded in accident. Shards still in the flesh surrounding the 'break', top section of sternum still lodged behind the second section. After 38 years living with it, I've gained some 'pain tolerance'...lol. ( a little light at the end of the tunnel for you?)
 
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