Topic: Cb750k6 advice

[paulreade]

I am in the process of trying to tune my k6. It's fouling plugs and invariably needs at least one and more often 2 taking out and cleaning upon start up (everytime) . I've reset the points and static timing spot on which has made a huge difference but just want to trial the Carbtune unit.
Q1. Using a Carbtune unit- I have equaled the pressures out at around 16 on the gauge - ( they were out before 1/3 reading 20, 2/4 reading 16. I am running the bike at around 1800 rpm when doing the adjustment, should I be looking to set at a higher or lower setting on the gauge and if so what actual effect does that have on the bike . I've just read I should be looking for 20-22 ? But don't know why as it's the first time I've used a gauge ?
Q2. Adjustment made at the top of the carbs ? Is that correct or should I use the pilot air screw or just leave those set as per the book ?
Q3.Can anyone confirm the torque setting for the oil filter housing and the drain bolt ( believe the drain bolt is around 25-32 ft lb) .
Thanks In advance

[Alan F.]

Yes, 25 ft/lbs on the drain bolt. Use a new sealing washer, clean smooth surfaces and keep to the low end of the spec as the threads have been known to pull out of the oil pan.

[69cb750]

Sync carbs with vacumn gauges at idle, adjustment is on top of carb.
20 lbs max on oil bolts, 15 is better.
If plugs are black and choke is open you have other problems.

[Stev-o]

First off, if you are fouling plugs, sounds as if your carbs have wrong jetting.  Is your bike stock and have original Keihin brass parts? If you have aftermarket carb kits, you are going to be chasing your tail on this.

Q1.  I dont have a Carbtune [I have Honda vac guage] but the main thing is the vacuum needs to be the same on all carbs.

[BenelliSEI]

1. When synchronizing carbs, I usually run at lower revs. 1000-12000rpm. My motion pro gauges have no numbers, focus on getting all four readings the same.
2. Synchronizing adjustments are made at the top adjuster nut. Undo the small lock nut first, them adjust the larger one. The frustration comes when locking down the small nut. It always changes the reading! I set air screws to manual spec first.
3. The oil filter bolt can probably take torque, but I use a bit less. Same for the drain bolt. Remember these are into soft alloy and easy to strip. I do them by feel, with a 3/8 drive ratchet only. 15-17 ft. lbs. is plenty.
4. Have a large fan set and running from the front of the engine. At first, this can take longer than expected!

[paulreade]

Cheers guys. I'll have another play with the gauges ( good practice) at slightly lower rpm. Just reading the manuals it states setting the vacuum at 20-22 cm HG - so will see how that goes.
I'm not sure on the jets etc, I have no idea how I would find that out either at this stage. Guess having got the timing bob on now , if I try and sync the carbs and see how that goes with the mixtures - all a good learning curve !