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  1. 1985 CB450SC needle length?

    Fuel Supply and Carburation
    I have been working on my buddies 1985 CB450SC, the previous owner tried to rebuild the carb and put A bunch of incorrect parts. I have already replaced the pilot and primary jet with the correct size. The only part I am unsure of/think might be incorrect is the Vacuum piston needle. It is...
  2. '85 CB450SC no spark in left cylinder, weak spark generally. Help!

    Electrical Discussion
    Hello, I have been working on my buddies 1985 CB450SC Nighthawk over the past couple weeks. The bike is able to idle, but whenever any throttle is given it starts to die. it seams to die inconsistently, one sec it would rev alright for a sec then the next it would die immediately. Do you know...
  3. Intro

    Member Introductions
    hey Stone from Ontario Canada . Have a 84 CB450SC needs work so I thought I would bob it , any others out there , like to see what can be done. Good to meet you all ,
  4. 1985 CB450SC bolt, cylinder

    Engine Discussion
    Hi there, I am new to this so be nice... ;) I have taken apart my 1985 CB450SC top engine as there was no compression in the left cylinder. My issue now is I don't remember if the longer bolts go at the back or at the front... Yeah I m a moron! There are 2 bolts with rubber at the bottom, can...
  5. Becoming reacquainted with an old Friend

    Member Introductions
    Hello, My name is Gene and I am from Boyertown PA, USA. I am an avid Motorcyclist. My love for the sport is not manufactured specific. I have never met a bike I did not like. I have been riding since the age of 6 and I am a lifetime member of the AMA. I enjoy working on and Restoring bikes as...
  6. CB450SC Regulator/Rectifier replacement video

    Electrical Discussion
    Hello! Got my new R/R in the mail today, and did a video of me going through the process of replacing the stock one, as well as the battery. Its a bit on the longer side, but I wanted to be thorough and document the small hiccups in the installation I went through. Hopefully at some point or...
  7. Fsm 1984 cb450sc?

    Manuals and Technical Documents
    Anyone have the FSM for a 1984 450sc? New to the forum. Thanks!
  8. CB450 Nighthawk won't start. Gas tank rust??

    Engine Discussion
    Hello! I bought a 1984 cb450 Nighthawk (Canada version, possibly the 1983 model) earlier this year. It started cold, worked great on a test ride, then I put it in storage for a few months (with little fuel, maybe 1 litre). The previous owner told me the carbs were timed very recently. Last...
  9. looking for tach for 82 cb450sc

    Wanted Parts and Bikes
    Hi there, I'm looking to see if anyone has a tachometer for an 82 cb450sc, or any advice on how to repair one? Mine started jumping and quit working, so I took it apart and saw that the spring inside has broken. Not sure how to fix it, so might be easier to see if anyone has an entire assembly...
  10. The 1984 CB450SC NightHawk Post-Modern Retrofying

    Project Logs
    Hi All! I just joined the forum as I recently picked up a working amazingly near-stock 1984 cb450sc with newly timed carbs, new chain+sprockets, tires, etc at 33KM. I know exactly what I want to do with it, but given that this model wasn't released in the US (i'm in Canada), there is limited...
  11. Taylor's 1982 CB450sc Build

    Project Logs
    Ok, first post for this thread. Here we go. Got the bike Spring 2017. Didn't run when I got it, figured out some electrical issues, cleaned the carbs, tried a new battery, replaced some fuses, and thanks to the folks here, got it idling roughly. The whole plan for getting this bike was to do a...
  12. 1985 Nighthawk 450

    Bikes For Sale
    Hello all, I know this isn't the best time of year to be posting this... but my wife is spring cleaning in the fall and wants more room in the garage for winter. I'm looking to sell my Nighthawk 450. I just don't ride it as much as it deserves. I have two kids and not a lot of free time (wife...
  13. Luggage Rack Support Brackets

    Miscellaneous Discussion
    I purchased my 1982 450 Nighthawk fifteen years ago from the original owner. It came with two sets of luggage rack support brackets. One set fit my Nighthawk perfectly and the other set did not. The bracket would hit the side cover but the bolt holes lined up. I was cleaning up my shop and...
  14. 1983 CB450SC Nighthawk

    Member Introductions
    Hi everyone. I joined the forum in Spring 2015 after acquiring a new-to-me 1983 Honda CB450SC Nighthawk. It's in reasonable shape and the PO painted it a really nice dark green (incl the original chrome front fender). I've posted in a few other topics and still have a few things to work out but...
  15. Horn

    Electrical Issues
    I've got a 1983 CB450SC From what I can tell the electrical system all works as it should except the horn. I can't get it to make any sound by pushing in the button. I disassembled the left controls to get at the horn switch. Looks in good shape - not much corrosion. I am now able to get the...
  16. New Tires for a CB450 Nighthawk ??

    Project Logs
    Hello All, Just wanted your collective feedback on new tires for my 1985 CB450SC Nighthawk. The stock Bridgestone Spitfires are in need of replacement and I was trying to decide if I should just continue with new Bridgestones or possibly switch to a Dunlop 404 tire. If anyone has experience with...
  17. I'm playing the "Which Part is Bent?" game again...forks or triple tree on a CB450sc

    Frame, Suspension and Steering
    I'm playing the "Which Part is Bent?" game again...forks or triple tree on a CB450sc Hello all, A while back I had some issues with a bent frame up near the head tube of my 83 nighthawk 450. 8 months and almost $600 later that problem is solved. The guy did an awesome job at straightening and...
  18. Very strange carb issue I can't figure out…..PLEASE HELP!!!

    Fuel Supply and Carburation
    So I pulled my 1982 CB450SC Nighthawk out from storage and noticed something strange while riding it for the first time this year. It started great, choke worked fine, but while riding it when I went to down-shift the revs stayed high (around 4000 RPM), with the clutch pulled and my hand...
  19. Fuel line routing on 1986 CB450SC with CA Emissions Canister

    Fuel Supply and Carburation
    Hey everybody, I've searched around a bit and couldn't find any thread that actually answered where everything goes. The service manual doesn't show the routing of fuel lines. Basically, I got a bike for free but lots of the hoses are broken or missing and the CA Emissions thing is really...
  20. cb450 nighthawk runs rich

    Engine Discussion
    I have an 85 cb450 nighthawk that runs to rich. I have gone through the carbs and cant find the problem. The jets are stock, floats are not adjustable and measure good, and I replaced the float valve needle. The pilot air mixture screw is set to the leanest setting and still the bike runs rich...