Topic: 78' CB750K hard throttle twist!

[zeus87]

I searched and really didnt find answers i was looking for.  Anyway, twisting the throttle is killer on anyones wrist ( i let multiple people experience it)  It is factory push/pull, it has awesome return snap, but is just far to hard to twist, what can be done?  I dont want to counter it with a spring the opposite direction, that would be deadly it the primary spring broke.  Anyway let me know what you think, i replaced the cables already.

[eurban]

Well you may have some issues making your particular 78 harder to twist or it may just be the normal spring rate.  I have no issues with turning the throttle on my 78 but it certainly is not as low effort as on many modern bikes.  You say it returns with a nice snap which usually indicates proper function but you may still have some problems adding up to extra effort.  Check your cable routing.  If your bars are close to stock, the stock routing for the cables is best.  Also, the plastic throttle tube that fits underneath the grip can have issues. Sometimes the tube can crack, sometimes the bar underneath the tube can be rusty, and sometimes there is simply too much resistance without some lube.  I use some light bodied grease on the bar end prior to installing the grip/trottle tube assembly.  The tube is a cheap part and should be replaced if it is damaged.  If all is in order then you are left with modifying the springs on the carb body. 

[bhorocks]

i would lube it.  my clutch cable would return to snap back to but was a behatch to pull. Pulled the cable off and spent prolly an hour combined cleaning it now it wokrs great.  It never hurts to clean the cables anyways. (or replace them)

[chrislib]

I`ll add another for checking and lubing the cables. I am slowly putting my bike back together and just yesterday I was reinstalling the throttle and clutch cables. What I found was the cables are in good shape, no fraying etc. but they were kinda stiff. I flushed them out with a liberal blasting of WD40 wich seemed to loosen up whatever crud was sticking them up (bike has sat unused for about 6 years). Then I dribbled some graphite laden lube (Lock Ease is the brand) down the cable wire (VERY messy). I was rewarded with silky smooth cable action...me happy camper now.

[zeus87]

reply, i guess thats just the way it is...and im just not used to it.  I replaced the cables, tube is fine, springs is wrapped the only way it can be...factory bars, with factory routing.  go figure...Thanks!

[zeus87]

has anyone changed out the factory throttle assembly?  If so let me know what parts or possible part numbers.  I wouldnt mind keeping it clean around the handlebars, relocating the start button etc.  Thanks

[BruceFenster]

I have a 78 750K as well and after owning it and putting up with the hard twisting throttle for 24 years I decided to do something about it. 4 years ago after confirming all was working as it should, I disconnected the stock return spring and replaced it with a new spring system. One of the best mods I've made to the bike in 28 years.

Yes I'm the third owner but have owned the bike continuously since 1980 and have been familiar with the bike since it left the showroom floor. The throttle was always hard to twist and took effort to hold in place. One of the reasons the two previous owners sold it.

[KeithB]

Just spent 3+ hours riding my '78 Cafe and I agree that the throttle is a bit hard to twist.
All cables are lubed and routed correctly but the '72 is MUCH easier on the hands.
Looking at a different spring.

[Johnie]

The PO of my KO had installed a "home-made" what he called a cruise control.  What he did was install a return spring down the shaft of the throttle / handle bar and connect that spring with the plastic throttle sleeve to take the tension off the users wrist.  Pretty neat deal and I still have it but did not put it back on my restoration.  I could get some pics of the system if you are interested to give it a try.  I do not want to sell it as I may put it back on someday.