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Messages - neildavies67
2
« on: May 14, 2018, 06:46:38 AM »
So, a forum member has generously sold me a set of nos CYB350/250 valves for a very reasonable price! Big thanks to that member! On to the next problem...
3
« on: May 09, 2018, 09:30:26 AM »
Yeah, I called them the other day. Not in stock at the moment and no idea when they will be! Maybe I should have got me a unicorn, spares would have been easier to find  CMSNL have Honda valves for a combined cost of about £160! Ouch!
4
« on: May 08, 2018, 09:18:04 PM »
Thanks for the info Trigger, it just led me down the rabbit hole into the land of valves and metallurgy! My brain is well fried now. Apparently, Kibblewhite black diamond valves are made from EV8 stainless which, if I read correctly, is an alloy commonly used in performance engines for exhaust valves and is also known as 21-4N (EV8). The full article can be found here: http://www.enginebuildermag.com/2005/12/valve-selection-hot-valve-materials-for-hot-engines/I'm not 100% but I think this means that they should be ok for intake valves? (although the article mentions different characteristics preferable in intake and exhaust valves). The guy that sells these valves races classics in the TT so I assume that they must be ok but admittedly, he may just replace them at the start of each season! I didn't ask him but I will now. Does anyone know what material/alloy factory fitted valves are made from? Cheers.
5
« on: May 08, 2018, 07:30:45 AM »
Hi, has anyone had any experience of replacing their standard oem valves with Kibblewhite "black diamond" valves? The inlet is 1mm oversize (35mm) and I am unsure whether I would need the valve seat cut to accommodate the 1mm over or whether you could "lap" them in? Any thoughts or tales of woe hard earned through experience greatly appreciated! Cheers!
6
« on: September 12, 2017, 10:31:46 PM »
Here's something interesting, an ebay listing for a new CB250 head K0-K4 but notice in the pics that the chamfer is present, unlike AshimotoK0's head - https://www.ebay.co.uk/p/Cylinder-Head-Honda-Cb250-K0-k4-B4-Cl250k-Part-NOS/605341165I make the diameter on mine (excluding chamfer) about the same as AshimotoK0's 250 head. Have you measured the depth? Statfold engineering have said that they would have a go at making good my cylinder head but I might look out for a good condition 250 head first! It seems a lot easier to just machine a chamfer than make good on a chamber with a resemblance to the lunar surface!
7
« on: September 10, 2017, 03:35:10 PM »
Wow, lots of advice for me to mull over! Thanks everyone, feeling much more positive this morning! My current plan is as follows: purchase cheap compressor (hopefully second hand to save cash) and soda/walnut shell blast the crap out of the head to remove carbon. I need to clean up all the other engine cases and various other bits and pieces so I can (kind of) offset the cost against time I would otherwise have spent doing it all by hand. Hopefully get a response from one of my enquiries re: combustion chamber repair, that doesn't cost mega bucks! Otherwise it's Dremel time as suggested! While I'm spending the kids inheritance, I intend to get the valve seats done, rebore, pistons & rings, cam chain and tensioner. By the time I've got the camshaft and followers done with Boyer Bransden ignition, apart from having spent stupid money which I'll never get back, hopefully whatever caused the problem in the first place wont raise its head again (but my wife may have left me!). Out of interest, the depth of the chamber is 20.3 mm, 64 mm diam with a 30 degree chamfer 4.5 mm wide. All measurements very approximate! How does that compare with the 250 head AshimotoK0? If they could be machined to match the 350 chamber dimensions, I would certainly be interested in taking one off your hands if you're happy to part with one. Thanks for the link Florence, that certainly looks like a good head relative to mine! Does anyone know if the heads are exchangeable across all the models (except the camshaft housing)? It's wierd that the add seems to indicate '71 onwards. I notice the head is stamped M 10, mine is stamped E 2. Is that significant? Once again, many thanks for all the advice and optimism. The body and mind are willing but the wallet is getting rapidly empty!
8
« on: September 09, 2017, 05:06:30 PM »
Thanks to everyone for their comments and advice! The consensus appears to be leaning towards"shagged". That's depressing but it is what it is! I agree with K2-K6 though, I haven't found any indication of mechanical damage, just the pitting. I would have thought that if there had been a stray piece of piston ring or plug in there at some point there would be more damage. Doesn't matter either way though I suppose, still shagged! I'm going to carry on drinking while I can still afford it! Thanks again everyone! 
9
« on: September 09, 2017, 03:15:17 PM »
Cheers for looking AshimotoK0. I'm going to hold fire until I get some responses from my engineering enquiries! Exhaust studs are 8mm. I'm off to drown my sorrows now! Cheers again for the assistance.
10
« on: September 09, 2017, 01:15:33 PM »
I bet that sounded nice when it went tit's up!
I wouldn't know (although I wish I had known). I bought this beast as is (a non-runner with reasonable copression)! I gambled and am now paying the price! I haven't given up on it yet though!!!
11
« on: September 09, 2017, 01:03:59 PM »
Cheers AshimotoK0! I've fired off some e-mails and pics to some engineering firms so will wait and see what comes back! There are a few videos on YouTube showing combustion chamber repair by welding extra material and re-machining so I am "glass half full" at the moment! I will update as soon as I receive some replies!
12
« on: September 09, 2017, 11:51:05 AM »
Hi folks! What do people think? Is this cylinder head salvageable? If so, can someone reccomend a decent engineer? If not, does anyone have a cylinder head for sale to fit a 1969 Honda CL350 money pit? Cheers!
13
« on: September 08, 2017, 09:32:56 PM »
Cheers AshimotoK0! Interested to see how it compares with mine!
14
« on: September 04, 2017, 02:38:30 PM »
Isn't the pudding the earlier model?
15
« on: September 04, 2017, 11:14:51 AM »
"Travesty" is a bit harsh, technically it's just an iced bakewell tart surely! Or are there Bakewell purists that are going to argue it's a pudding and shouldn't be covered in fondant icing? Surely Mr Kippling couldn't get it that wrong?
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