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Discussion Starter · #1 ·
I went through a little bit of this in my introduction thread but I'll go into more detail here about the HamHock and what I have done and plan on doing.

In september 2015 I purchased a 1982 CB450SC Nighthawk from a college kid in Berkeley, CA for $1000. The (broken) odometer read 39k. I also got boxes of spares with it, a second frame, fork, engine in pieces and various other odds and ends. About a month later I was lane splitting on 880 and high sided when a cager changed lanes without signaling and I collided with the rear drivers side door of his mini van. I went down and slid into the median. I tore my jeans, got some road rash but was able to ride away after calming down a bit. The damage to the bike was pretty limited. I only had to replace the bars and right side turn signals. I got used turn signals and took the oportunity to get some ACE clubman bars that I installed upside down. I removed the rear plastics at this time aswell.

Before the crash, as I bought it.

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After the crash.

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Not long after this the side cover tbs broke off and after a few weeks with them taped on one flew off on the freeway and I took the other one of too. I looked into replacements but the cost way more than I cared to pay.

Right around this same time I was on my way home from work and I made a right turn and gave her the beans when all of a sudden I lost power. The bike didn't die but became gutless and was making a horrendous clanking noise from the top end. I was about a mile from home and limped there slowly. when I pulled the valve cover I found that the right side inner intake valve adjust had come completely out of its mounting. I found the set screw sitting in the cylinder head but the nut had seemed to work its way down the cam chain passage. I put the set srec back in and took a nut from my parts engine, adjusted valve lash and everything was fine.

Around this time I also cleaned out the carbs, installed an inline fuel filter, replaced the rear tire and wheel bearings, put in new plugs and 5k resistor caps, rebuilt the fork with new seals and wipers, went to bar end mirrors, recovered the seat, air filter, clutch plates and springs, swapped the handle bar clamps for ones from an '84 V65 and blocked off the tach drive with a block off for a cb750. I ad to grind it down a little to fit.

In early 2016 I went to colorado for a while and left the bike in the care of my friend who was learning to ride. He painted the tank white and gray (to match his trans am lol) and dropped it a few times in his driveway. He also replaced the battery and the brake stay rod.

After I got it back from him the mirrors were broken off and it needed the valves lashed and a good amount more TLC. Since getting it back from him I have replaced the clutch cable, headlight and bucket (halogen H4 with integrated LEDS), headlight bracket, swing arm bushings, front and rear sprockets (moved to 17/34, I spend a lot of time on the freeway), rear brake shoes, front brake pads, removed the mufflers after the H chamber (this caused the center stand to rub on the chain so it was also removed, though LDR has shown me a way to modify it and reinstall it), chain and also had a chrome cm400 fender with an ebay tail light but the tailing melted and I had to switch back. Additionally I have an M1945 field pack zip tied to the seat for storage.

Somewhere in all of this I started to notice white/blue smoke from the exhaust intermittently. Mostly when real hot and running it hard. Did a compression test and I have 145 PSI (far below the 170 PSI minimum) in both cylinder when hot. Knowing I need rings pretty soon I bought a running (they said) 1986 CB450SC engine for $200. My plan is to run this engine into the ground (I have AAA roadside assistance), swap it out and then rebuild an engine using my current and parts engines.

Near the end of 2015 I had picked up a 1984 VF500F Interceptor for $250 but I screwed up and forgot about the registration while in Colorado and when I was back in CA they wanted $400 in registration and I couldn't get it started. And now I am in the middle of putting the VF500F fork on the CB450SC. I got a set off all balls tapered steering bearings for the swap and a bunch of other parts I will document in a later post. Knowing the difference in wheel and fork size and its effect on rake and trail I have some 280MM rear shocks on the way that I will install with the new front end. I will gain twin disc front and 37MM stanchions and I believe the front end will drop nearly 4 inches. This suits me well as I have been trying to get this bke as light as possible and more nimble. I have been reading a lot from Tony Foale's book "Motorcycle Handling and Chassis design". It's been a big help in the way I think about the dynamics of a bike.

In September of this year I purchased a 1986 VFR700F2 and got T boned 5 days later, breaking my tibia and sending the bike to impound. By the time I got out of surgery and hospital they wanted 1K to get it back and I couldn't afford it. I'm still recovering from the break, have a nasty limp and limited stamina but I was back on two wheels within two months much to the chagrin of orthopedist.

The front end swap should be done in a couple weeks.
Future plans include:
GM coil mod (probably aftermarket CDI at some point too)
Rear sets
VF500F tank swap (and a different seat to go with it
1978 cb400 swingarm swap (1 inch less wheel base)
The engine rebuild I mentioned
relocating some of the wiring
And who knows what else as time goes on.

I will keep updating this thread over time as this bike progresses. I am still riding this bike almost daily so I can't just tear it apart and go at it.

here's the headlight

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Here's a couple of pics with the VF500F tank mocked up.

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Have to keep track of this one.
I think the CB400 swingarm is even shorter than 1", closer to 2" since the chain is 4 links less. 106 vs 102
 

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Discussion Starter · #3 ·
A month or so after I bought the bike I noticed that I had an intermittent tail light. I traced the problem to the ignition switch and a loose connection of the brown/white wire inside the of it. I could usually get the light to come on by jiggling the bottom of the switch. I eventually removed the switch to inspect for corrosion. I didn't find any corrosion but found that the black plastic piece on the bottom was loose because the little ears holding it in had seen better days. I put it back together and used a zip tie to hold it in place. This worked reasonably well for a while but I started searching for a more permanent solution. I did not want to buy a used one and risk having the same problem and I was unable to locate a NOS one.

About six weeks ago I found an ignition switch on eBay that said it would work 0n 82-83 CB450SCs (as well as earlier CB/CM 400/450s). It was only $6 so I figured I had nothing to loose. Itt showed up this week and I ran into some roadblocks right away.
Problems I noticed:
  • The body of the ignition switch had more girth than the stock one, this meant that I could not mount it to the top triple clamp.
  • Only 5 of the 6 wires were in the block. the black/white had a bullet connector.
  • The back of the new ignition switch was completly open, inviting corrosion of the solder joints.

Here's the new switch. You can see the wire I'm talking about.

Light Automotive lighting Diving regulator Headlamp Auto part

I cut off the bullet connector, took one of the spades from my old switch and soldered it onto the black/white wire and stuck it in the block.



To try and seal the back at least a little I took a thin piece of plastic, traced the bottom and cut it out. I then took an old bicycle inner tube and cut and shaped it and then glued it to the plastic.

Climbing hold

Mounting it was still throwing me for a loop. I looked around at various stuff I had on hand and eventually took a bracket off the front fairing of my VF500F. I mounted the switch to the bracket and mounted the bracket to the right front gas tank mount.

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Here you can see all the pieces and the bracket better.

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I will probably end up welding two nuts to the frame to mount it in the future but for now this works and so does my tail light.
 

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Discussion Starter · #4 ·
Have to keep track of this one.
I think the CB400 swingarm is even shorter than 1", closer to 2" since the chain is 4 links less. 106 vs 102
530 chain has a 5/8" pitch so I would guess you are probably right. 2 links top and bottom would be at least 1 1/4" shorter and possibly more.
 

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Discussion Starter · #5 · (Edited)
My new shocks came last night.

Machine

They are just some cheap eBay crap I picked up for $60. That's all the budget allowed for right now. In the future I will probably upgrade.
The shocks themselves are 280MM eye to clevis, and have 10MM of ride height adjustment as well as independent preload adjustment and damper adjustment. They are not a direct bolt on. The eye is too narrow and the clevis uses a smaller bolt than stock. The shocks came with three sizes of bushings but all three are too small. I will measure the stock eye size and use a piece of pipe to make a bushing. I think that'll work. The clevis is also about .5MM too wide. I will try to find a thin washer to slip in.

Tracking info shows my new brake hose should be here today.
New EBC kevlar pads showed up yesterday.
I've got a new Bridgestone Battlax BT45 100/90 - R16 mounted.
I also have new a master cylinder and clutch lever.
New grips as well and mirrors on the way.
I'll be using an allballs tapered bearing kit for the swap.

Drum Exercise equipment Sports equipment Drums Electronic instrument


This morning I've been pouring over wiring diagrams for the VF500F and the Nighthawk. I plan to use the controls from the VF. I've made a crib sheet in excel and so far I've got the left side control sorted out and I've deleted the horn button and it's wiring and then plugged the hole with JB weld. I also took out the screws that hold the controls together and replaced them with hex head cap screws. The right side control is giving me a little frustration though. The VF500 wiring diagram is crystal clear about what wires go to which switch but the diagram for the CB450SC is not. I can make out the colors going to the control but I am confused as to which wires are for the kill switch and which are or the starter button. Also the VF500 has 6 wires going to those two switches where the CB450SC only has 5. I'll just use the CB450SC right side control if I haven't figured it out in time for the swap. I'd appreciate any help with this though.

EDIT:fixed second picture.
 

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If the picture was sideways and you rotated it on the computer then you probably forgot to hit save which locks the new orientation. Ctrl S is save if you don't have a Save hot button
 

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Discussion Starter · #7 ·
I believe the problem stems from my phone. When I take pictures in a portrait orientation (tall and narrow) and upload them here they get put in a landscape orientation. On my phone and pc they appear as I took them but once I post them here they get rotated. I even tried to rotating it, saving it and uploading but it still posted the same way as before. I'll just make a note of this and take all my pictures in a landscape.
 

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Discussion Starter · #8 ·
I spent most of day working on my stupid jeep. I did however get time to install the brake pads, hoses and bench bleed the new master. Next step is going to be removing the lower bearing race from the stem. It's looking like I will need to cut it off, but I haven't tried anything else yet. Anyone have tips for bearing race removal?
 

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Large chisel and hammer works most of the time, just have to get/keep the stem supported firmly so it doesn't jump around
 

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Discussion Starter · #10 ·
I decided that while an old inner tube had its merits in sealing electronics I wanted something more permanent for my ignition switch. So I went and got some liquid tape.

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Much cleaner looking and should do a lot more to keep things working properly.

I also took the opportunity clean and paint the bracket I have it mounted on.
 

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Discussion Starter · #11 ·
I don't have a dedicated work space and my front end is at my friends place. He's been in Oregon for the last week so I haven't been able to work on the swap. I did get the left side controls from the VF500 working on the Nighthawk (except the clutch switch) but I really hate the turn signal lever. Its the modern type where it returns to center and then you have to give it a half click to turn it off. I always end up pushing it too far and turning on the other turn signal before I get them off. I wanted to use the VF controls because of the integrated choke lever but this signal lever situation has me disappointed.

The solution was obvious.

Sand wedge Metal

I'm no where near done and the bottom needs a lot more attention too. This control was also developing a problem with the Hi/Lo switch so I took a scuff pad cleaned all the connections inside.

I did get these installed this week too.

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Always nice to see a Fellow 82 450SC, ill be following this build, keep up the nice work
 

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Discussion Starter · #13 ·
My buddy is back from Oregon. I went by today and went over my spare engine, getting it ready to swap in. I got the lower race off from the VF500 stem today. Only took about 5 min with a chisel and hammer. I was really expecting to fight it off after some stories I had read. I have the stem in his freezer now, we're going to throw the VF500 front end on tomorrow.

Can anyone who has done the tapered roller bearing conversion answer a few of my questions?

How do I determine which and how many of the provided washers to use? I.E. how do I get the stem length right

Any tips for driving on the new lower race/bearing?

Any tips for driving the racers into the frame? I've seen people use a socket but I don't have one that large. When I used to work on bicycles I would use a piece of wood and a hammer to drive it in. Any harm in doing the same thing here?

I was thinking today about my new shocks as well. The stock Honda shock uses a 10x32 bolt to hold the clevis onto the swing arm. My new shocks are threaded for an M8 and I got the proper sized bolts and some washers to take up the slack in the clevis. What I got to thinking about today is that the inside of the eyelet on the swing arm is sized for an M10 and I'm going to use a smaller bolt. Is this going to be an issue? My tap set got stolen about a year ago otherwise I would just drill it out and tap it for M10. If you guys think this could cause me trouble though I would go out and get a tap for it. Is the smaller bolt going to hammer itself and break? Safety first!

Thanks for the help and I'll be sure to take lots of pictures tomorrow of the before/during/after of the swap.
 

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Start new topic in SOHC Suspension for the fork conversion since it'll help others. Pictures will be good
Now the fun begins. Compare side to side the old and new to see where the bearings align. Measure the upper and lower complete bearings for stack height.
You want to try to get a good idea of where the lower is going to be setting in the frame, possibly some grinding needed for clearance. You may have to make or modify the steering stops. The lower bearing stack height will give you an idea of where everything sits and if any washer/spacers are needed. This will also give you a good idea of where the upper bearing is going to sit.
Freeze the bearing races for as long as possible before driving them in. Wood is best but you may need to use the old races to finish driving them in. Alternative is a long bolt with plates that you tighten up to pull the races in by tightening a nut. When the races are finally in and bottomed then carefully use a file around the upper edge of the race to remove any burrs.
The factory recommendation on tightening the bearings to a point where the front end falls to one side easily does not apply with tapered rollers. Tighten until there's significant drag side to side then loosen slightly, maybe 1/8-1/4 turn. There'll still be noticeable drag but you can push it side to side with 1 finger.
 

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Discussion Starter · #15 ·
I've been worried about the stops, but I've got a few grinding options so it shouldn't be hard to solve. I am always a bit hesitant to just start cutting or grinding my frame.

Making a new thread is a good idea. I will do that once I have everything buttoned up. I am planning to take measurements of offset of both the stock and VF clamps, accurate measurement of fork length as well as rake and trail both with stock shocks and the shorter ones. I think I am going to have to ride with the stock shocks for at least a few days as I want to the nitrogen filled to 75 PSI in my new shocks, 4 Wheel Parts in Oakland should be able to do this for like $10 shock. There is literally no place flat enough to measure rake and trail at my friends house. I figure I can do it in a parking lot but how can I hold the bike upright with both tires on the ground?

Do I need to pack my new bearings with grease?

Is it bad to use heat on the new lower bearing/race to fit it on the stem?
 

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Yes the new bearings need to be packed with grease, I use the BelRay water proof stuff.
Heat on the bearing isn't a good idea, the race and rollers will be fine, it's the cage that can get distorted
Measuring rake/trail is a 2 person operation usually and in your case definitely
 

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Discussion Starter · #17 ·
The VF500F Front end is installed!

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Disassembly went smoothly. Had no problem driving out the old races and driving in the new ones.


New top race in. I was worried about it sticking up but I recalled LDR having the same issue when he put on his CB900 front end.

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Getting the lower bearing on the stem was easy enough. I had frozen the stem overnight and used the old bearing race to drive it on. I originally used the largest washer in the kit but it was too much. I had to remove the bearing and replace the washer with the smaller one.

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I packed the bearing with some white grease from Orielly's, it was rated for high impacts and was water resistant. Figured it'll do fine.

The steering stops had to be cut down on the bottom. They currently are fine but need more trimming for low speed maneuverability.

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I broke my headlight shell while trying to install it. Stupid Chinese plastic. Ever notice how good OEM parts are and how bad some of the "universal" parts are?

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I need to figure out some sort of a dust seal for the top and bottom and cut down the steering stops more. I also need to replace one of my brake bleeders and re-bleed the brakes (one was corroded shut). I've ordered a replacement headlight, another cheap one for now.

I've only got about 15 miles and that was all city and high way. So far the bike is more maneuverable and handles better. The Honda TRAC (Torque Reactive Anti-Dive Control) system is killer. The front is stiffer and more compliant and allows for more correction mid corner. Maybe those designers were onto something with those 16 inch wheels in the 80's. Less rotating mass theoretically allows for quicker changes in direction. I am still using the stock length shocks and honestly I am unsure about the shorter ones I have. The way the bike handles right now is pretty great. I will measure rake and trail and try out the new lower rear shocks and see how I like it though.

Once I have some dust seals and more measurements I will make a thread detailing everything about the swap as per LDR's advice.

Before:

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After

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Discussion Starter · #18 ·
Replacement headlight showed up. Sorry for the bad pic and dirty bike. I've put on 200 rainy wet miles since the swap.

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For the lower bearing dust seal try one of the old fork dust seals, cut the tapered section off. That's what I did with mine, had to glue it in place though. My top one didn't need anything since the upper triple covered it nicely.
You can use a small bubble level on top of the case under the carbs to check if the rear needs to drop. If it shows high in the rear then it is high, normally that area will be close to level or the rear a tad low.
 

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My buddy is back from Oregon. I went by today and went over my spare engine, getting it ready to swap in. I got the lower race off from the VF500 stem today. Only took about 5 min with a chisel and hammer. I was really expecting to fight it off after some stories I had read. I have the stem in his freezer now, we're going to throw the VF500 front end on tomorrow.

Can anyone who has done the tapered roller bearing conversion answer a few of my questions?



How do I determine which and how many of the provided washers to use? I.E. how do I get the stem length right

Any tips for driving on the new lower race/bearing?

Any tips for driving the racers into the frame? I've seen people use a socket but I don't have one that large. When I used to work on bicycles I would use a piece of wood and a hammer to drive it in. Any harm in doing the same thing here?

I was thinking today about my new shocks as well. The stock Honda shock uses a 10x32 bolt to hold the clevis onto the swing arm. My new shocks are threaded for an M8 and I got the proper sized bolts and some washers to take up the slack in the clevis. What I got to thinking about today is that the inside of the eyelet on the swing arm is sized for an M10 and I'm going to use a smaller bolt. Is this going to be an issue? My tap set got stolen about a year ago otherwise I would just drill it out and tap it for M10. If you guys think this could cause me trouble though I would go out and get a tap for it. Is the smaller bolt going to hammer itself and break? Safety first!

Thanks for the help and I'll be sure to take lots of pictures tomorrow of the before/during/after of the swap.
Definatly tap it and use the 10mm bolt.
 
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