(Not so) Budget drag bike project - DOHC 450, of course

I think Summit stocks VDO, marine shops as well (although those always get hit with the boat tax markup).
 
Yeah, I checked there too but the only 30 psi range gauges were $170+. I looked around the auto parts stores while out yesterday and nothing easily found locally without burning way more gas than time on the computer, so I found an alternative gauge supplier this morning and ordered this cheapie:


Reviews seem above average and accuracy isn't critical as long as it's halfway decent.
 
Put the oil filter cup on this afternoon and tightened the spanner nut (first time I've ever actually used a torque wrench on one), then dug through my spare gaskets for both crankcase covers. While digging through the drawer-full I found some Vesrah gaskets left over so I used them instead of the NE spares I have, and while fitting the right crankcase cover gasket to the case and cover I noticed how inaccurate both versions were around the incoming and outgoing oil filter passages in the cover. So, I laid the gasket on the cover and tapped lightly with a ball peen to make some witness marks, then cut out the areas to match the castings. Probably wouldn't matter with the added oil pressure the engine will be working with, but I might as well while I'm there.

After a successful test drill and tap of a right cover using the half cover from the pump tests in preparation for the 30 lb gauge on the way, I hoped for the same good luck with the second effort. Tried my damnedest to jig it up so I could use the drill press but just couldn't find a solid combination using what I have, so I clamped the cover between a couple blocks of wood and hand drilled it. Slightly lower angle than the first effort but the hole came right into the middle of the passage so it should work well. Nice wide section of threads on the top and bottom where the tap used the wall thickness of the passage in the cover. Test fitted an elbow from the petcock hardware for the tiny tank Russ made.

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Inside view

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Flushed it with carb spray and blew it out thoroughly, but I'm going to go back in there one more time with a file to try to knock off any remaining swarf just in case

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Nice work! Will you be using a fitting of some kind with the gauge or will it mount directly to the threaded hole you just made?
Thanks, the gauge is directly on top of its threaded inlet so it will face forward, but it isn't like I'll be concerned with reading it on the fly.

And Merry Christmas!

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I got the new left crankcase cover installed this afternoon, Vesrah gasket and a light film of Hondabond because Jay's pump, better to do it now than later if I just left it dry like usual. Put a little bit on the two 6mm bolts and flat washers in the cover to close the crankshaft ignition mounting holes too. And I was pleasantly surprised that the overhang of the original gasket shape covers the upper and lower gaps left open by the new cover.

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Most of the aftermarket right crankcase cover gaskets I've seen don't have full-sized openings for the incoming and outgoing flow from the pump, so I opened them up to mostly full size as available material allowed.


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Finished off the right side today. Lots of shiny scratches in these, the oil filter cover because it's the one from my cabin driveway fall at 5 mph a couple years ago and the right crankcase cover because it was quite corroded.

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I guess if it doesn't run as well as hoped for, at least it will look pretty good from 10 feet.
 
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Looks good. Just wondering if there is a right angle fitting available so that the gauge would point upward, it would give you the opportunity to view the pressure a little more easily.
 
Looks good. Just wondering if there is a right angle fitting available so that the gauge would point upward, it would give you the opportunity to view the pressure a little more easily.
I know but I figured adding more length to it, with the weight of the gauge on more leverage because of the added length, might cause trouble for the threads in the cover since it was drilled into the curved casting for the oil delivery and the hole only has about 4 good threads in the thinner areas at the 3 and 9 o'clock positions. I'm not going to be looking at it during a run, so I figured for general purposes facing forward would be adequate to check it once in a while during maintenance.
 
I'm a little hesitant about the forward facing, seems like asking for a rock to hit the face.
Yeah, I thought about that too but since a typical run doesn't have anyone directly in front of you kicking up stuff on the pavement (that shouldn't be there anyway because they sweep the track before and during test and tune nights) it's unlikely anything would hit it. I suppose I could make a small rabbit wire cage to put around it like the cafe guys use over their headlights as if they're ready for the apocalypse.
 
Working on matching up the ports to the carbs. It's a shame these pretty valves won't stay that way.

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Not quite there yet

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And brand new torsion bars, I can honestly say I've never installed any previously and there is a noticeable difference in seat tension compared to the ones in my red 450.

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Sorry if this a dumb question, but…..when you say “ not quite there yet”…. will you machine the intake to match the boots to the same diameter? Or is it a boot figment problem?
 
Sorry if this a dumb question, but…..when you say “ not quite there yet”…. will you machine the intake to match the boots to the same diameter? Or is it a boot figment problem?
Yes, matching the boot to the port but there will be no actual machining LOL, I'm using cave man equipment. If you look closely at the end of the intake port, there's a faint Sharpie line visible on most of the circle so I have a little bit more to remove to get that one matched, then do the other side. I've already opened up the head side of the rubber manifolds with a conical-shaped fine reamer-like cutting tool (which I don't know the proper name for) in the drill press.
 
Yeah, rotary sander. They come in cartridge form. They’re like soldiers and one needs an army.
But, they do a fantastic job of controlling material removal, even with a drill.
 
Yeah, rotary sander. They come in cartridge form. They’re like soldiers and one needs an army.
But, they do a fantastic job of controlling material removal, even with a drill.
I'm not sure what this is called (could have tried an image search I guess) but this is what I've had for a very long time, and a smaller more blunt-ended one much like it as well.

Edit: I remember the term "die grinder" growing up, didn't think of this as one but an image search says so.



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or if I really need to hog out something, there's always this

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After numerous hours over numerous days, I'm calling done on the ports. Yeah, I could spend a little more time taking off .010" here and there to make it perfect, but if you accidentally go a tad too far then you have to make it up somewhere else so I'm quitting while it's pretty good. Still have to open up the gaskets to match.

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And the carb's POV

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It was quite touchy tapering the rubber insulators, trying to open them up to the necessary size without taking off so much that it compromises the structural integrity. The inner edge of the molded rubber at the port is about half as thick to the seam around the metal tube as it was before I started. And I still have at least one more tedious job to do, carving off part of the lobe on the points cam for the advancer.
 
Great job, Tom.

What sort of surface finish is ideal for porting? The idea is to create smooth flow, yet I've read that too smooth a finish is undesirable.
Thanks, I just hope it works like I want. As to the finish, back when I built my first one the prevailing thought was polished ports and we started hearing about it being less efficient around the time I was out of drag racing for a long time. I wish I had a picture of the 450 head I had ported, polished and bench-flowed by then-legendary Jerry Branch, it was an amazing and beautiful piece that never got used (and was a bargain even then, he did it for $125). The ports in this head were a smooth finished "rough look" when I got the head back from Schumann, and the outer areas of the intakes show more tool marks now from the slight opening up, tapering and matching process but I've sanded them with worn emery paper so they feel smooth to the touch despite the visual shown in the flash pictures. They look a bit different but are about the same finish as his work by feel, so I'd guess they'll be about right.
 
Mirror finish not advised.
Satin/smooth matte flows well. It’s port turns that the (thin) boundary layer helps make efficient.
 
Gave the head a final wash in solvent followed by a sprayed water rinse and air pressure dry, then started assembly. The dull surface from being bead blasted hid a few gouges from previous gorillas working on this engine part, spent some time lightly filing surfaces to see them all but a little Hondabond will solve those problems.

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Yeesh. That’s a hefty gouge on that cam bearing cover surface. At least they left a little of the sealing area intact.
 
Yeesh. That’s a hefty gouge on that cam bearing cover surface. At least they left a little of the sealing area intact.
Yeah, it ain't the best but a little sealant should take care of it, which I'm doing to almost all the top end parts anyway because of Jay's pump.
 
Yeah, it ain't the best but a little sealant should take care of it, which I'm doing to almost all the top end parts anyway because of Jay's pump.
Good call.

I notice you haven’t done pistons yet - are you planning stock bore/type or cooking up some race magic there as well?
 
I notice you haven’t done pistons yet - are you planning stock bore/type or cooking up some race magic there as well?
It's been so long that I'd almost forgotten they were mentioned a few pages back. My only concern here is the potential need to get another set bored if this job isn't a quality one (cylinders bored by someone since revealed as somewhat of a hack, big cash/parts/labor trade I made with the guy in early 2019 for my VF1100S - which later outed his crappy valve seat cutting and bead-blasting of the head before it was washed clean of oil and goo, which Schumann made me aware of and cleaned up for me during the work). I'll be uncovering and washing up the cylinders soon for the first mock-up of the top end to check piston to valve clearances at TDC, so hopefully I'll be able to tell if the bore job is worth taking a chance on. If not, I'll be begging Mike Nixon to do it for me on a spare set of cylinders.

These came from THR, bought them through Buff Harsh who used to ride for Naughtin's AHRMA team before Terry retired, and took over sales at THR for a while. Pretty sure they're done selling stuff now too. They're likely from Wiseco, they have that look.

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and the big cams from Terry Naughtin, .414" lift, 280° duration

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Wow. That lift with new torsion springs - you’re going to have to brace the rotor bolt pretty good when doing the timing!

I had forgotten about the saga with the prior machine work. Likely out of sympathy… hopefully they’re useable. It’s tough as hell to find someone willing to tackle the 450’s.
 
I am much taken with everything you are doing on this engine build but I found myself staring at the cam lobes, smooth as a baby's bottom, and not something we usually see here regretfully with most of us using used cams. Also what kind of compression are you looking at with those pistons?
 
I am much taken with everything you are doing on this engine build but I found myself staring at the cam lobes, smooth as a baby's bottom, and not something we usually see here regretfully with most of us using used cams. Also what kind of compression are you looking at with those pistons?
Those cams are an old pair I had on hand and sent to Terry Naughtin to have welded up and reground. He didn't admit to who did it for him but I believe it was Megacycle, they have a very similar grind. But Naughtin's price was over $100 less, $430 shipped. The 74mm pistons are said to be 12:1 but could end up a little lower if I have to get the valve pockets relieved a bit for proper clearance.
 
I would be curious to see a plasticine test of the combustion area, can't be much room left with those high domes on the pistons.
 
I would be curious to see a plasticine test of the combustion area, can't be much room left with those high domes on the pistons.
I've never cc'ed a head before, never used anything more than the seller's information for fitting pistons and verifying valve clearances because the cams and pistons I've used previously were all known to be compatible back in the day. My first drag bike had Powroll 74mm pistons and when I bought them (through a phone call of course, no internet in '73 LOL) I was told they would need to be flycut .060" for Megacycle's 120-40 cams, with modest lift increase at .350"/.365", to be safe (and they're the same exact cams I'm running in the red 450) so I had them do it for me before delivery and was not concerned when I built that engine. With these cams being significantly higher lift, I'm definitely going to check the clearance. The red 450's Team Hansen pistons are said to be 11.6:1 and they have similar dome height, though obviously I can't put them side by side to compare.

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Since the head is ready for mock-up assembly to check piston to valve clearance, I pulled the cylinders out of hibernation (they were bored in late 2019) and washed off the mix of Lucas oil stabilizer and Brad Penn oil I'd coated them with back then. Brought them inside to do the soapy hot water wash LDR recommends and tried to dry them as fast as possible so they wouldn't flash rust. Then the bigger challenge was getting decently focused pictures of them. I ended up using the flash and took a short video as well.

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The cylinders feel super smooth, none of the things seen can be felt. But despite them both being marked as 73.95mm from Wiseco (confirmed by the W on the cute little drawstring-equipped bags each one were in) and there being Sharpie measurements on the domes that show a .0004" difference between the two, as well as #1 and #2 marked on the domes assumedly meaning 1=left and 2=right... I have no way to check the clearance to be sure said machinist set the clearance correctly for forged pistons. I'm quite sure it was discussed between us prior to him doing the boring, but I looked back through my archives and it was never verified in any of the email discussions we had.

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When in doubt recheck, take everything to a good machinist to remeasure the bores.
Personally I don't like what I see of the honing finish, not enough cross hatching at 30*-45 degrees. Looks like the up/down stoking was very slow.
 
When in doubt recheck, take everything to a good machinist to remeasure the bores.
Personally I don't like what I see of the honing finish, not enough cross hatching at 30*-45 degrees. Looks like the up/down stoking was very slow.
That was my impression on the cross-hatching too.

Now I just have to find a good local machinist.
 
I wish I still had a good machinist. The best one I knew had medical issues and retired then my closest one also got medical issues and doesn't do anything anymore.
The motorcycle machinist is getting to be scarce, at least near me.
Same here. Finally found a guy way out in the boondocks that will work on the vintage stuff.
 
Same here. Finally found a guy way out in the boondocks that will work on the vintage stuff.
After digging through the memory archives in the last 24 hours, I remembered that the son of the deceased previous owner of United Speed World in Tampa, where I had my red 450 cylinders bored, lives not too far south of me so he might know of a decent machine shop up our way. I'll have to check with him before driving the almost 60 miles to Tampa to have USW's house machinist look at my current set. And the new owner might want to charge me for having Teddy just look at them, who knows. I built their first website back in 2008 and the new ownership still owes me for paying their domain fee for a couple years after they bought the business from the late owner's widow, but their reputation isn't nearly as solid and honest as the previous ownership.
 
The machinist that did the cylinders and head on my 450 is a young guy that is local and seems to have his stuff together. He listened to what I had to say and asked the right questions and although I haven't really put my engine to the test I am confident in his work. If you are having trouble finding someone in your area he might be worth checking out.

 
The machinist that did the cylinders and head on my 450 is a young guy that is local and seems to have his stuff together. He listened to what I had to say and asked the right questions and although I haven't really put my engine to the test I am confident in his work. If you are having trouble finding someone in your area he might be worth checking out.

Thanks Rob and I'm sure he's good, but if I'm going to ship them anywhere I'll just send them to Mike Nixon. Problem is, unless Mike has a set of cylinders to use to replace mine, I'd have to ship two sets of cylinders to him. I'm going to text Junior today, son of the late former speed shop owner, and hopefully he knows someone local.
 
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