20 Most Recent 2007 Honda CB 750 Questions & Answers

You may have a bent shift drum actuator arm - inside the case.

You will need to download the Service Manual. You can find it at:
http://pdftown.com/PDF-Honda-CB750-Shop-Manual.html
It's in 6 parts. They are all there and your information is in them.
Good luck with your rebuild!

In the long run... get an automatic chain oiler. You´ll have to clean your rear once in a while, but its much easier, than maintaining your chain. It´ll be cheaper, too. Oh, and your chain will last longer as well!

If you need to use choke and there has been a recent clean and/or rebuild. It would be a good idea to check the fuel mixture screw setting. It sounds like it is running a fuel/air mix that is too thin, (lean mixture).

left coil feeds 1 and 4...right coil feeds 2 and 3...as long as you stick to this it doesn't matter which lead goes to which plug. Left coil will have one short lead and one long...short =1...long = 4. Right coil leads will be about even in length...doesn't matter which goes to 2 or 3. It's a wasted spark system so plugs 1 and 4 fire together...2 and 3 fire together...only 1 cylinder in each pair will be compressed and ready to fire when the spark happens, the other will be empty and coming on to it's inlet stroke...

dot 5 brake fluid.

Use DOT-3 brake fluid!

1-4 fire off one coil 2-3 fire off the other coil

Sorry I thought the bike was a 1975 when in fact it is a 1982. I would suggest you check the points and make sure it is clean and adjusted properly. Regarding the carb, you can make 2 become 1 but if the parts will fit and bear in mind that air mixture will require careful tuning since it will not be the same as manufactured default. Back firing is often caused by faulty spark, plugs, coil or even bad ground to engine.Also before you consider doing any work on the carb, try to swap the points to a new one.(I assume it has a points engine due to the year of manufacture)

1. Carbs not cleaned correctly 2. airbox not sealed to back of carbs or no air cleaner in it 3. intake manifolds broken or open and leaking air 4. any open vacuum lines will make a backfire 5. a lean condition on the engine 6. possibly valve problems or cam timing

A: buy a manual. B: Go to Nighthawk Forum on line, register (free) and discover all the great people there willing to help you.

do you mean the short rubber intake pipes between air box and carbs ? if so then number each one and make a note of angle they sit , remove them and put in hot water untill feel soft then fit back in , also loosen air box b4 this and they should be easier to push on , bit fiddly but should go on now ! If the pipes wont come off try a hair dryer ! P...