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1981 CM400A Rebuild

replaced old taillight lens/socket with new one from 4-in-1. New one didnt have any rubber bumpers for shock so i chopped off some old foam bike handlebars i had and used pieces of that. Also replaced front day/turn lamps with the LED versions. everything tested and works.
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Got all I need for my headlight casing replacement so thats next project once i get a nice day. This weekend is filled with CMSP safety course.
 
is there anywhere online that lists the old amco racks and what models go with what bikes?
 
is there anywhere online that lists the old amco racks and what models go with what bikes?
Doubtful but one day someone may find an old catalog laying around that didn't get tossed like most out of date/manufacture catalogs. Then if it is found they would need to scan and upload it to the net. If you find old literature like that I will always accept it so I can scan and add to our library. I don't know if you've looked closely at the SOHC section in the library but there's stuff like the Predelivery assembly instructions for the 1978 A model
 
i'm taking a shot on a tripleA rack i found on ebay, matches the vin# for fitting and free returns so hopefully it works.
 
added luggage rack. used some old foam grips cut up to protect the u-bolt chrome. I'll add some red LED brake lights to the end in a week or so.
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replaced the remaining instrument lights with led, now only the headlight remains. I was going to add an led taillight strip to the back rack but the ones i got would not mount securely so i'll look for a better one.
thinking of replacing my master cyl. it works fine but looks bad. would love a chrome one but can't find a chrome one that has a fluid window.cyl.jpg
 
The led headlight I got will not fit into the stock chrome headlight bezel. An mine has a small ding in it too. Any recommendations on a LED light and bezel pair that fits will and leaves enough room for the wire mess behind it?
 
question: the 2 screws holding the honda badge to the tank, is it ok to replace all that without affecting the tank at all? The screws dont go into the tank, right?
 
hows my pads lookin? isnt there supposed to be a red line to read somewhere? ordered a replacement MC today. Also discovered i melted a little of the cheapo cover i initially bought. rookie ^^

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fixed the missing seat lock chain link, now the seat is locked to the helmet lock. Also did a tank inspection and looks great. I do not see or smell gas in the oil so for now i'm leaving it as it since im not riding it in this 50 degree weather. Also got a smoked blue visor for my HJC i10, looks badass now.
 
replaced the remaining instrument lights with led, now only the headlight remains. I was going to add an led taillight strip to the back rack but the ones i got would not mount securely so i'll look for a better one.
thinking of replacing my master cyl. it works fine but looks bad.

would love a chrome one but can't find a chrome one that has a fluid window.View attachment 11648

For the master cylinder. You could strip and buff it.. I bet it will take a polish. Or just paint it again.
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thanks but m/c are fairly inexpensive so i ordered a chrome one. might be a little tricky bleeding the brakes by myself but i'll try.
 
of course the impossible find would be a 53180-417-870 parking brake lever in chrome to match the front brake.
 
thanks but m/c are fairly inexpensive so i ordered a chrome one. might be a little tricky bleeding the brakes by myself but i'll try.
Yup. Alan F mentioned an 11mm core would be a good option, most I find that are inexpensive are in the 14mm size, but the 14mm are plentiful and I lose patience reading the small print.
Yet, I too am looking to replace mine at some point.

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finally greased up the speedo cable proper today, 1st try failed, read 80 or 0. reinstalled the link and works fine now. no jittering.
My headlight options are as follows: The black plastic case (7" wide) is cracked so left turn signal droops. The LED light i bought will not fit the stock rim without deforming it more. so that option is stock light with a small dent or nada. I have the new black plastic repl. base.
The chrome dish/housing i just got has a 8" width so i would need to not only heat up my side support and bend it out, but also pray that the wiring fits through the small lower hole (the black one has 2 holes for all the wires). Otherwise i'd need to dremel or drill out the metal to fit the harnesses, havent tried it yet.

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nice ride though today, got it up to 65
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If you go with the metal bucket be sure to insulate the edges of the hole the wires go thru to prevent them being cut with vibration. Easiest wat is small vacuum hose split lengthwise and glued to the edge.
 
attempted to put on the LED luggage rack lights only to find out they are DOA. cheap china crap (although metal and chrome).
Took off logos and did some black touch up on them.20220102_140332.jpg

hmm, must have had a bad ground because they work on my battery. i'll try the chassis ground tomorrow.
 
waxed tank/panels so feel better about the rainy season.
re-installed logos after touch-up
installed LED luggage rack lights (detachable with the rack) so you can see my brakes now if I add a big bag on top.
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Well, the chrome dome that i ordered has smaller turn signal threads than the stock ones so my only option is to replace the black housing and keep the stock headlight, which I did tonight.

Anyone want to buy a 7" chrome headlight with LED?lights1.jpg
 
added LSK fuel gauge tonight, works fine, I can do a write-up if anyone if interested. Will look for a center bracket for it but for now, its left side.

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so, 1st time with my phone mounted, speedometer is about 7mph fast at 40 (gps said 33). is this normal?
 
Yeah, that's fairly typical. Over the years, at least 5 mph optimistic on average from all the discussions I've seen.
 
Typically you can expect a 10% over actual speed on any motorcycle, cars to for that matter. Tire circumference makes a difference as well.
a 3.50s18 tire converts to a 90/90/18 but depending on the manufacturer the circumference could be off as much as 50mm/@2" larger or smaller.
 
I must be lucky because mine is right on the money. 1980 CM400A but that really shouldn’t make much difference.

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^^^Is it really chrome, or is it polished? Either way it looks great, just curious as it looks polished really well
 
hard to tell really but its all metal and very shiny. if polished looks that good i'm ok with it.
 
I'm swapping out my headlight and the retaining clip on the halogen bulb came off and i cant figure out how it goes back on. looks like.
of course i figured it out after posting.
 

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ok, front brake hose clamp has a rubber grommet in it, can't find the part #. clamp is part
45417-413-000

i need the rubber part shown here:bgrom.jpg
 
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New Halogen headlight. it has a parking light but i didnt hook it up yet, gonna get a yellow led for it first.
also installed St2 turn signal canceler.
also moved my LSK fuel gauge to the center using a galvanized bracket.
 

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ok, front brake hose clamp has a rubber grommet in it, can't find the part #. clamp is part
45417-413-000

i need the rubber part shown here:

I see the problem, both CMSNL and Partzilla do not show #4 from the fiche in the parts list so you can't find a part number. Fortunately we have a CB400A parts catalog in our library, I'm quite sure the "brake hose bush" as Honda calls it would be the same as yours. p/n 45146-371-000

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added windscreen and tested TPMS. TPMS is a 1-2 psi off but easy to see. Wind screen works great for keeping wind off my body but does shift it to my helmet a bit, didn't affect handing too bad. 1 more mod to go, i'm going to add a 12v cig lighter socket under the seat so i can run a mini pump if needed.
 

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took ker out to test a higher angle, too much buffeting. i'll lower it back tomorrow.
 

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There's a low pressure zone directly behind the windscreen at speed, the air forced over the top starts to spill back in 12-18" from the top of the screen. If this spill is in front of your helmet then buffeting will occur, ideally the spill should be on top of your helmet or just behind.
While riding use your left hand to feel the air flow, follow the path.
 
adjusting my chain tension for the 1st time, the tire is close to the chain guard. my chain notches are close but i really want a more exact way to know the axle is centered other than it not rubbing. Whats the best way?
 
Do a 'chain alignment tool' search on ebay. There's a variety of tools from cheap but effective through to laser liners. A long steel rule can be just as effective along the chain between sprockets.

Example of cheapy:
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adjusting my chain tension for the 1st time, the tire is close to the chain guard. my chain notches are close but i really want a more exact way to know the axle is centered other than it not rubbing. Whats the best way?
I have found on the CM/CB 400/450 series that the chain/axle alignment notches are spot on. It's just a case of matching the positions on each side as closely as possible. You mention that the tire is very close to the chain guard, I'm guessing the tire is a 130/90/16 instead of the stock 120/80/16 or 4.60S16
 
OK, good size. The chain guard typically has @1/2" clearance but if a PO bent it that may be less. Both sides should be parallel to each other and the inner edge should fit in the slotted piece on top of the arm.
 
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