Cb360 Reassembly Help

valve

https://www.ebay.com/itm/OEM-HONDA-CB350-CL350-SL350-CB360-CL360-CJ360-INTAKE-VALVE-BRAND-NEW/392262008210?epid=1011810962&hash=item5b54a33d92:g:Tf0AAOSwM7lccELj

Guide

https://www.ebay.com/p/12205-362-305-NOS-Honda-Valve-Guide-Cj360-Xl175-Y381e/1163497972
 
Ho hum, I was pretty convinced it was exhaust side hitting piston. Intakes, having the 34mm head have more leverage to bend. You did de-burr around the cotter groove before trying to pull valve from head? If the top end of stem is bent that's an assembly issue. The adjuster screw caught on the 1/2mm or so sticking out from spring retainer. It's the reason I've always taught people to back off adjusters before stripping engine and have tips level with bottom of rocker arm on re-assembly. (since the early 70's when I was teaching my brothers and sister) $38.00 seems a bit high for stock valve? (guess I'm still in the 70's ;D ) I wish sellers would give stem diameter, head diameter and length, it would make finding replacements or oversize valves too easy. ;)
 
Bummer but at least you found the problem. Might as well check that your other valves have a really good seal. I'd really be considering just sending the head to a machine shop and having them work it over, cut new seats and all at this point.
 
If you can't DIY it you better have a good job to pay for something like that.
I would guess around $250 ~$450.? 10~15 yrs ago it cost about $25.00 'per hole' to have valve seats cut, valve guide replacement $20 each, cutting, etc extra. $200 or more a set ( think that may be with 45deg seats done?) To do it properly is going to take at least 4 hrs so I guess it depends on labor rates?
Unless you know the shop very well I would be very wary of a cheep price. You can get automotive done cheaper as they can set up for at least 8 valves of much larger diameter, many automotive shops won't even look at motorcycle stuff and many bike shops are only interested in high dollar restorations or Harley's (in which case equipment would be too big) If I could get my head together (and I mean mine not a cylinder head) I would offer but I've had a 360 head here about 3 yrs so far. I made a set of aluminum bronze guides but my step-grandson has hidden them somewhere, he loves the garage and workshop. Also looking into 35mm intakes from something different, may not work but I'll find out.
I think I have ordinary bearing bronze but would prefer to use 'the good stuff', particularly since they are already done. If you do fit new guide, make sure head is heated to about 250f, and guide is either drawn in with bol and shaped washer on valve seat or pressed in with correct holder sitting on valve seat. Hammering the iron guides is likely to crack them even though it was 'correct' in 1970's.
 
Are bronze guides worth it? Or am I better going with the stock nos ones?

When I had my cylinders bored and matched to my pistons, i had a valve job done as well. I will look again tonight, but I really don't think I gave them new guides for the valves. Which makes me think it is best I go ahead and replace them all for good measure, as I want to ride this bike worry free from now on. Plus I dont have the right tools to install a new guide. I could definitely lap the valve myself, but the new guide I dont think so.
 
Talked to a machine shop today, the one that did the work for me previously. $125 for the labor, $12 per valve guide install. So $175 is reasonable... But add up the cost of the valve, which I bought, plus all the other damage done.. $226 plus the $175... man breaking stuff costs lots of money. My dad likes to say "being stupid hurts huh?".

Oh, and the shop recommended bronze valve guides only because they don't wear out as quickly as iron. So bronze guides here I come.
 
Should be able to get a set of CB350/360 bronze guides cheaper than the NOS 360 Honda ones. They have way better heat transfer and wear about the same as original cast iron. (depending on type of bronze) Don't know how long I've recommended getting hold of a cheap single to play with when doing any sort of modifications, it's way cheaper to only buy one or two of anything but the amount of education you get is the same as if you had a $10,000 engine
 
crazypj said:
Should be able to get a set of CB350/360 bronze guides cheaper than the NOS 360 Honda ones. They have way better heat transfer and wear about the same as original cast iron. (depending on type of bronze) Don't know how long I've recommended getting hold of a cheap single to play with when doing any sort of modifications, it's way cheaper to only buy one or two of anything but the amount of education you get is the same as if you had a $10,000 engine

I've never gone into engines as far as I'm about to go into.

Good advice, I bought a CL350 trashed engine for cheap, and am practicing on it to get a feel for when I break into the CB350 engine I intend to rebuild and use.

Helps to gain confidence too.
 
Let it be known, valve seals are to expensive for what they are. $10 a piece??? Gotta be kidding me
 
cb360j said:
Let it be known, valve seals are to expensive for what they are. $10 a piece??? Gotta be kidding me

Here's a set for $10. Also on ebay you can get all 4 valve guides and seals for like $45.

https://www.ebay.com/itm/HONDA-CB360-CL360-CJ360-CB-CL-CJ-360-VITON-VALVE-SEALS/232457755799?epid=26004701708&hash=item361f8fdc97:g:~PIAAMXQ9qpRSUQW:sc:USPSFirstClass!77357!US!-1
 
Should be able to get better than OEM as they are still being made and used on something. I think I paid $12.00 for 4 for the blue ones which are higher temp 'plastic rubber' ;D Crikey, that's unusual, price is lower now than 3~4 yrs ago
 
I wish i had found those before. Thankfully, i had a gift certificate for one of the dealerships here in town that my sister gave me, so I only ended up spending like $13 or something.
 
advCo said:
Here's a set for $10. Also on ebay you can get all 4 valve guides and seals for like $45.

https://www.ebay.com/itm/HONDA-CB360-CL360-CJ360-CB-CL-CJ-360-VITON-VALVE-SEALS/232457755799?epid=26004701708&hash=item361f8fdc97:g:~PIAAMXQ9qpRSUQW:sc:USPSFirstClass!77357!US!-1

Same ones I installed maybe 7yrs ago.
 
Welp, Sloan’s called me (the local dealer) and said they couldn’t get my valve seals so they refunded me. And then with the gift certificate I got a pair of 100% goggles, since I needed some new ones anyway. And got those for free, which is dope!
Then just ordered the seals y’all recommended.
 
Top end went to the machine shop today. Bad news.
The other intake valve is worn badly and needs to be replaced. One exhaust valve has a large burn spot that took a chunk from it. So if I’m replacing three valves I might as well replace the 4th.
And also, he said he was checking the valve springs and they are no longer in spec. I figure I can find valves fairly easy, but I have no idea where to get springs. Does anyone have any inclination as to where?
 
WOuldit be worth buying a new (used head) all together and then using the parts off of it? My only worry is that it might have the same problems.

Are there any parts that are compatible from other bikes? Like the springs off a 550 or 450 or 350? Even a 750 maybe
 
350 and 360springs are the same and dead easy to find. Very doubtful you'll find a good head cheap and even then it will most likely have 40 yr old valve springs. They should have a spring tester will know fitted length poundage and 'over the nose pressure. Honda probably still have something in production that uses same spring although finding it may not be easy. Stock wire diameter varies slightly, about 4.33mm for outer and 3.05 for inner springs. Outside of windings seems to be 32.00 nominal but measured at 32.20 to 32.30mm outer and 21.25 to 21.30 for inner springs . What lengths did he give you? I forget service spec but the ones I've measured are in the 47.75 to 48.50mm range. 'Race' springs are often shorter but have very slightly thicker wire (maybe 0.005"~0.010") better material? If I could afford it I would contact Comp Cams and see if they haev a single 'behive' or newer conical spring that could be fitted, lower poundage but better valve control as they don't surge or get into valve bounce so easily. Long (Very long) time ago I actually did the math for 360 valves, they should be 'safe' up to 37,000 rpm ???
 
Pj my dad said the same thing about contacting comp cams. I also found that boretech makes valve springs for a cb350 so that’s an option. I just don’t want to drop an arm and a leg on these things.
What information do you figure comp cams would need? Would I need to send them an old valve for comparison
 
You can get valves for CB350. For springs, you could probably send a pair of old ones, valve weights and max expected rpm? Never know, you may be the newest supplier of 'race' springs for AHRMA CB350 since Bore Tech shut up shop. Todd Hennings ain't getting any younger either ;D Several businesses here started with small parts for CB360's or similar......... If they don't have a stock part I doubt they will be interested in order for less than a few thousand though Some manufacturers are happy to get into a different market while others (Piper cams, Quaife transmissions) who built their businesses on motorcycles won't even answer e-mails about the stuff they made 40~50 yrs ago for motorcycles (since they got into WRC, F1, etc)
 
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