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

So many little challenges keep popping up, bead-blasted dowel pin holes that need to be cleaned out, poor-fitting aftermarket base gaskets including both Vesrah gaskets which surprised me (though the NE base gasket is actually a bit worse) and gummed-up cylinder sleeve o-rings from bead-blasting that had to be dug out, literally. Finally got all of it cleared up and dropped some big pieces together in prep for mock-up. Also noticed how much shorter the wristpins are for use with this version of teflon buttons. The previous set of teflon buttons I used in the early '70s had a smaller diameter portion that fit inside the wristpin end, these are wider but without the "plug" end.

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Between the cold weather and other life occurrences, not much going on with this right now. I took the pistons and cylinders to the speed shop in Tampa today in hopes that the machinist could check them while I waited... but now, instead of the 4 person crew they previously had, there are 11 people working there now and the machine shop is slammed. Dozens of automotive cylinder heads there for repair, 10 high performance V8 builds in process all at once with the customers all in a hurry and they had to hire a second machinist to try to keep up. So I had to leave the cylinders and pistons with Todd and they'll call me (for another 130 mile round trip) to pick them up when he's done. Considering we have yet another cold front coming, one that will be colder than any previous one this year so far, I guess it isn't a big deal because garage time would be limited anyway. Should have gotten to that sooner I guess. :rolleyes:
 
If only I had just stayed overnight in Tampa yesterday. I just called the speed shop to let them know the required clearance for Wisecos and (dumbass me forgot) to help them identify which cylinder was #1 (left), and they'd already measured them this morning and found them to be at .0023" clearance, which Todd said was fine and he'd run them as is. He also said the bore was straight and the honed finish (with almost horizontal cross-hatch) was actually better for my purposes, minimal break-in and right to thrashing it.

But now I have to make another 130 mile round trip again soon. :rolleyes:
 
frankjames1900 said:
Sad about the trip but, not the parts. It seems you have a good machinist.
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Actually, the good machinist far away was checking the work of the possibly questionable machinist from 2019. But yeah, he's good - built hundreds if not thousands of high performance V8s for United Speed World in Tampa, and bored the cylinders on my red bike 9 years ago.
 
I had some very good machinists but they are all gone now. There are a few around but they don't seem to want to do anything with the smaller bikes.
 
frankjames1900 said:
I had some very good machinists but they are all gone now. There are a few around but they don't seem to want to do anything with the smaller bikes.
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The best machinist I ever knew was one third owner of Honda of Tampa back in the '60s and '70s. He ran the parts department and handled all cylinder boring for the dealership, and he turned out some nice work for a long time. He bored the cylinders on my first drag bike and many, many engines I built back then. He opened a small one man machine shop after the trio sold the dealership but sadly has been gone now for a couple decades.
 
Had a little time during one of our few warm days yesterday to (basically destroy, LOL) fit a left crankcase cover over the Electrex cover so I'll have an index mark for TDC. The pointer is dead in the middle of the stator bolt hole at about 10 o'clock, it might be a degree off but since you can't degree the 450 cams it's basically for setting the cam and ignition timing before removing it. I used only 2 screws in opposite corners to attach it, and opened up the backside of the other screw holes to fit over the other screws already in the cover to avoid any loss of Hondabond adhesion.

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After over 3 weeks of near freezing or below temps here, the last couple days have been about getting my wife's plants back out in the real daylight from the safety of the well-insulated garage. And a little time yesterday to again work on the top end a bit. The cylinder base dowel pins have been a real PITA and I've had to clean up a few of that size and length to find two of them that fit easily, because this top end will be assembled and reassembled more than a few times in the coming days to be sure of piston to valve clearances. Finally got the dowels smoothed and the entry points in the bottom of the cylinders cleaned out enough to make that happen. I'm always amazed at how some areas that should never get any abuse somehow, sometimes, seem to with the age of these poor engines and the list of ID10T's working on them along the way. Had to use a drill bit and file to smooth out minor gouges inside the dowel pin holes in the cylinder base before the dowels would easily seat, yet the crankcase openings for those same dowels (that weren't touched by THAT OP) were fine.

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And after some pondering, I've decided to put a 90° fitting on the oil pressure gauge so it does point upward. I have a piece of strap steel I'll fab a brace from. It's just finger-tight right now, it'll need to be removed before the engine goes into the frame.

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On the oil pressure valve, do you think it’s going to need a locknut up against the oil pump cover?
 
Sometimes, in the midst of so many things to keep track of when you're building an engine from spare parts from multiple engines, you tend to take some things for granted - like checking the cams you send off for refurb/upgrade. I'm so used to working with these things that I didn't even give the cams a second look. Turns out the cams I had done have the faintest timing marks on them I've seen in a while and it took me few minutes today to determine which marks were correct.

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For those wondering about the zip ties around the torsion bar forks and followers... I figured it would be easier to leave the torsion bars out of the head for the moment while I check the piston to valve clearance, and before slipping the master link in the cam chain so I can slowly, carefully rotate the engine to each TDC position while lifting the valves to their seats as needed. No rings on the pistons, a used 74mm head gasket (pre-crushed LOL) and for now only followers on the intake side. When that side is checked (and hopefully cleared) then I'll do the exhaust side.

But it's about to storm here like crazy so the garage day is over.

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boddy said:
The faintest of marks, but right on the money! If it was my cam, I would reinforce those marks with a small file to make them more prominent.
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Thanks, that's a good idea. Hopefully I'll remember to do it in the midst of all that is left yet to do. This project has dragged out so long that the only benefit has been the amount of time I've had to think about certain things and come up with a few good ideas, but I guess there's that if nothing else. 🙄
 
ancientdad said:
This project has dragged out so long that the only benefit has been the amount of time I've had to think about certain things and come up with a few good ideas, but I guess there's that if nothing else.
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It's not the destination, but the journey - although it is nice to finally arrive ;)
 
After multiple weather, household and doctor appointment occurrences over the last few weeks that prevented me from getting much garage time at all, I'm finally back to the engine.

My borrowed dial indicator was requested to be returned (and he told me he'd bring it back over when he was done using it to check a front brake disc, now over 2 weeks ago) so I ordered an inexpensive one from Amazon. Probably would have worked if only the @#$%& magnetic base (which I did not want but the others were a LOT more expensive) is a POS and won't stick strongly enough to the metal plate I found that I bolted to the intake port. After much frustration, cursing and many times getting it almost set up only to have it fall off again, it went back in the box. Yeah, the hard plastic case it came in that they decided to ship in a paper envelope - despite it weighing a few pounds because of the mass of the base. The evidence of it being brutalized on its way here was clearly visible on the outside of the plastic case. When I opened it I fully expected the precision part of it to be damaged but amazingly it wasn't.

So, moving on to actually making some kind of progress. After a few failed attempts to modify an old torsion bar for less valve seat tension (including drilling the retaining bolt hole larger to allow it to "relax" a bit, as well as trying the opposite of what I'd read in the past when people wanted to make them tighter by grinding off a spline - which did work, but made it too loose, no seat tension at all) I used an old set of torsion bars (hopefully weaker just for testing and measurement purposes), timed up the cams and put a link in the chain so I could at least rotate it. That went well, but having never used cams with this high a lift previously I can tell you, @EzPete was right - man is there more rotation resistance now compared to even my red bike which does have modestly higher lift than stock. Guess I'm going to teach myself to use Terry Naughtin's clearance check method, little hockey sticks of solid core solder through the plug hole and between the valve and piston. That's gonna take some practice.

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The funky look of the cam lobes is a combo of oil I put on them during assembly over the coating Terry had done following the weld-up and regrind process.

And hey, the 4 old used torsion bars didn't snap during rotation so that's a plus.
 
ancientdad said:
After multiple weather, household and doctor appointment occurrences over the last few weeks that prevented me from getting much garage time at all, I'm finally back to the engine.

My borrowed dial indicator was requested to be returned (and he told me he'd bring it back over when he was done using it to check a front brake disc, now over 2 weeks ago) so I ordered an inexpensive one from Amazon. Probably would have worked if only the @#$%& magnetic base (which I did not want but the others were a LOT more expensive) is a POS and won't stick strongly enough to the metal plate I found that I bolted to the intake port. After much frustration, cursing and many times getting it almost set up only to have it fall off again, it went back in the box. Yeah, the hard plastic case it came in that they decided to ship in a paper envelope - despite it weighing a few pounds because of the mass of the base. The evidence of it being brutalized on its way here was clearly visible on the outside of the plastic case. When I opened it I fully expected the precision part of it to be damaged but amazingly it wasn't.

So, moving on to actually making some kind of progress. After a few failed attempts to modify an old torsion bar for less valve seat tension (including drilling the retaining bolt hole larger to allow it to "relax" a bit, as well as trying the opposite of what I'd read in the past when people wanted to make them tighter by grinding off a spline - which did work, but made it too loose, no seat tension at all) I used an old set of torsion bars (hopefully weaker just for testing and measurement purposes), timed up the cams and put a link in the chain so I could at least rotate it. That went well, but having never used cams with this high a lift previously I can tell you, @EzPete was right - man is there more rotation resistance now compared to even my red bike which does have modestly higher lift than stock. Guess I'm going to teach myself to use Terry Naughtin's clearance check method, little hockey sticks of solid core solder through the plug hole and between the valve and piston. That's gonna take some practice.

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The funky look of the cam lobes is a combo of oil I put on them during assembly over the coating Terry had done following the weld-up and regrind process.

And hey, the 4 old used torsion bars didn't snap during rotation so that's a plus.
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Nice to see that there is some progress with the build. Torsion bars don't snap that easily, only when the surface is damaged, or due to fatigue, or a combination of both.
 
Thats’s one of the challenges of high lift/duration cams on torsion heads. When I was building VW’s we had a couple of them that were 2-3 person operations just to set timing because holding TDC was almost impossible solo. For checking clearances, if you don’t already have the cam chain riveted you can remove the head gasket and it’ll take just a whisker of tension off (and give a 1MM buffer).

Lead tape also works for checking clearance through the plug hole, added benefit of being super maleable and a bit easier to “read”.
 
jensen said:
Torsion bars don't snap that easily, only when the surface is damaged, or due to fatigue, or a combination of both.
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Thanks. I was mostly joking about one of the torsion bars breaking, I've never seen it though I do know these camshafts are not recommended for long term use with torsion bars - which is what made me say that. But Terry Naughtin ran a set of these cams for a season of road racing using stock torsion bars so I'm trusting his experience.
 
EzPete said:
Lead tape also works for checking clearance through the plug hole, added benefit of being super maleable and a bit easier to “read”.
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Hadn't thought of lead tape, thanks. I dug through my father's collection of soldering supplies and found a roll of solid core solder thick enough for both the .060" and .080" clearance checks. It's still good to know that there's at least some clearance with these pistons, they're one point higher compression ratio than the ones in the red bike that are paired with the lower lift 120-40 grind (.330" compared to these at .414")
 
There is no photo of the metal plate you were using bolted to the intake port for your mag base, but part of the issue could be that it wasn’t big enough or thick enough. My experience with magnetic bases is that it takes certain amount of mass in the surface you are attaching to in order to make the base work correctly. I have found thin pieces of metal are especially ineffective for holding a magnetic base.
 
12ozPBR said:
There is no photo of the metal plate you were using bolted to the intake port for your mag base, but part of the issue could be that it wasn’t big enough or thick enough. My experience with magnetic bases is that it takes certain amount of mass in the surface you are attaching to in order to make the base work correctly. I have found thin pieces of metal are especially ineffective for holding a magnetic base.
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The metal plate was big enough, but thickness may have been part of the issue. It's about 3/32" and coincidentally had the exact bolt hole width of the intake port.
 
ancientdad said:
The metal plate was big enough, but thickness may have been part of the issue. It's about 3/32" and coincidentally had the exact bolt hole width of the intake port.
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That’s fairly thin. Thicker plate would have helped it stick a bit better so don’t trash the mag base without trying on something else.
 
12ozPBR said:
That’s fairly thin. Thicker plate would have helped it stick a bit better so don’t trash the mag base without trying on something else.
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Oh I'm not trashing anything, it's getting returned to Mr. Bezos. And if you mean the base's "reputation", oh well... I've only used a small number of precision devices in my life and I'm not good at using most of them, lack of practice. And the method I was hoping to use in this instance would still be challenging unless I had a better setup, but I'm going with Plan B now.
 
It's been a few days and the weather here is finally (almost beyond) spring-like. Perfect time for a visit from my SC brother in 450s, @12ozPBR. And I had a bunch of CB450K0 parts for him to take home, along with a few other items accumulated over the years (aside from the soon-to-be-recycled empty adult beverage containers).

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@wentwest - Bob, Chris took home the rest of the battery box you got the air cleaner connecting tube from LOL

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And of course, no guest should go unpunished by a ride along side the little red monster... a couple of (mostly sedate) rides actually, totaling close to 180 miles between them (and roughly 10 gas stops mixed in :ROFLMAO:) during which we stopped in downtown Brooksville to get better pictures of the huge Civil War mural on the side of Patricia's building.

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Chris' longtime friend John back home is (slowly, moreso than me if you can believe it) working on a drag bike of his own, as well as a road racer project, so Chris took some pics of my drag bike roller to share with him.

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My cute little cheapie voltmeter, which after further review was a fair parasitic drain if left connected all the time... so it's a momentary-check device now.

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The light version of 12ozPBR in attendance

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And the not-quite-accurate manual navigation list

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So instead of spending the time and effort to add captions to the video, here are some informational points.

Prior to Chris' arrival I spent a couple hours doing an extensive local road search to find a few new ones for us to ride. Plenty of turns, but no comparison to the twisty fun we have when riding in his area in upstate SC. It quickly became 55 miles of fun interrupted, not the least of which were the multiple fuel stops :)

After we left my house, at the 40 second mark I realized I'd forgotten to turn the petcock on

Lots of stops to check my charted route because CRS

Pesky ear plug came loose at about the 4 minute mark

7:20 mark realized I'd incorrectly entered a road that wasn't there (but only after going around a block a few times and pissing off some fenced-in dogs)

8:30 mark I discovered my headlight wasn't on prior, good thing most of the roads were very rural

About the 9:40 mark we found a section of "unimproved" road not described as such by Google maps, LOL

Aaand then the GoPro battery died :(

 
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I was long overdue for a visit with Tom at the Florida VHT nerve center. I appreciate the hospitality of Tom and his wife Patty, the tasty meals served, and the opportunity to spend evenings talking shop over sudsy, albeit now, light beverages. It is always fun on motorcycle rides to try and keep up with Tom on his hopped up DOHC 450. It is a nice workout for my old K2 450, pushing 9K rpms on acceleration to hang with his street legal drag bike. This visit my bike performed well and I had no issues unlike previous visits. That didn’t prevent Tom from finding things to critique however…

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I guess I shouldn’t expect anything less if my bike spends a few nights in Tom’s shop. Even though I feel my clutch is working better than ever after going through the entire mechanism in the past year, Tom felt the action of the cable and lever could be better. It didn’t take him long to have tools in hand working on my bike! All I could do is watch and sip a cold PBR Light. Not complaining though, life could be much worse 🤣

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Tom failed to mention the highlight of the visit which was me “allowing” him the opportunity to ride the K2, which he never had despite my insistence on previous trips. Good thing I waited until the end of the visit for him to do this because otherwise it probably would have resulted in him adjusting the operation of the rear brake (noted: adjustment needed, thanks!).

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Overall a great visit with days out enjoying what we should be enjoying, Vintage Honda Twins!!!
Thanks Tom 👍
 
12ozPBR said:
I was long overdue for a visit with Tom at the Florida VHT nerve center. I appreciate the hospitality of Tom and his wife Patty, the tasty meals served, and the opportunity to spend evenings talking shop over sudsy, albeit now, light beverages. It is always fun on motorcycle rides to try and keep up with Tom on his hopped up DOHC 450. It is a nice workout for my old K2 450, pushing 9K rpms on acceleration to hang with his street legal drag bike. This visit my bike performed well and I had no issues unlike previous visits. That didn’t prevent Tom from finding things to critique however…
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It's always great to have someone so immersed in DOHC 450s hang out in the garage with me, there's always something to talk about even if I run out of stories of scandalous times in my youth. But I will admit to succumbing to the urge to clear up the creaky lever action on Chris' clutch. I regret not going to the next level with a squirt of @ballbearian's recommended and magical P-80 cable lube, since his could use a tad. I'd have put the bike on my lift but sadly, there's still engine parts still strewn about the area.
12ozPBR said:
I guess I shouldn’t expect anything less if my bike spends a few nights in Tom’s shop. Even though I feel my clutch is working better than ever after going through the entire mechanism in the past year, Tom felt the action of the cable and lever could be better. It didn’t take him long to have tools in hand working on my bike! All I could do is watch and sip a cold PBR Light. Not complaining though, life could be much worse 🤣
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Yes, with a clear lift we'd have spent at least half a day checking out a few other things... like those rear brakes for sure.
12ozPBR said:
Tom failed to mention the highlight of the visit which was me “allowing” him the opportunity to ride the K2, which he never had despite my insistence on previous trips. Good thing I waited until the end of the visit for him to do this because otherwise it probably would have resulted in him adjusting the operation of the rear brake (noted: adjustment needed, thanks!).
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Unfortunately our rides always totally distract me from our pre-ride discussed intent to trade bikes while we're out, I forgot when I was up in SC last time too. I'm glad Chris reminded me when we got back, and we should have just gone back out for a short ride-switch together. We'll get to it next time for sure! It's a lot different riding and evaluating another bike when you actually take it out into a normal road situation rather than 3 minutes around the neighborhood. But his CB450K2 runs well, and it's a good thing he discovered the cracked exhaust camshaft sprocket a few months ago during regular maintenance. It would have sucked for that to rear its ugly head while out rural riding in Florida!
12ozPBR said:
Overall a great visit with days out enjoying what we should be enjoying, Vintage Honda Twins!!!
Thanks Tom 👍
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Always great to have you visit brother!
 
There's never enough time to do everything you want to do when someone visits, and I wish we'd been able to go to the new local drag strip while Chris was here. My local riding buddy Ray ran one of his bikes there last night for the first time since it opened and I went to watch, mostly to see how the track was run and what kind of hardware showed up. Though the guy who started the place is more like a carnival barker and loves to see himself on camera, I have to admit that the track seems to be pretty well done in design and execution, as well as it seems to be run in a pretty professional way. And fortunately for me, it's roughly 50 miles closer than the longstanding track south of me in St. Pete/Clearwater, and about 70+ miles closer than the really professionally-run 1/4 mile in Gainesville.

A few sights and sounds from last night. Screens are everywhere, along with a lot of car memorabilia. This is inside the Gear Head Grille

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There's a lot going on all around the facility, almost too much IMO - never a quiet moment at all, but there's seemingly something for everyone. Live band playing to no audience far left in the pic below, building behind it has an indoor kart track and arcade, drifting/burnout pad to the left out of the picture (doesn't interest me at all), plenty of food trucks, various merchandise sellers, tons of bikes ridden in (but mostly Harleys) and a raised seating bar area to the left of and behind the starting line among lots of other stuff.

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This rail set a new track record last night, 5.03 seconds

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Looking toward the starting line, 3 bulb tree and it was run the right way. Good to see some professionalism at an otherwise-theme park oriented facility.

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Nice report from a night at Leadfoot City! It seems Like an interesting concept and looked like fun when we did a ride by last weekend. I am not aware of anything like that near me in Upstate SC but from the sounds of apparent street racing on the interstate near my house we certainly could use a place like that!
Hopefully LC can keep the momentum from their opening and continue to grow the business. I am sure I am not alone in eagerly awaiting a video of either your street legal LRM or better yet, your current not-so low budget drag bike project making a run at Leadfoot City. Make it happen! 😃👍
 
12ozPBR said:
I am sure I am not alone in eagerly awaiting a video of either your street legal LRM or better yet, your current not-so low budget drag bike project making a run at Leadfoot City. Make it happen! 😃👍
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Yeah, I expect there are as many as several people here awaiting that, as am I of course. :rolleyes: Hey, it's been 6+ years now, another spring or summer's time is tiny by comparison! But it will happen. Eventually.
 
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