Tip & How-To about Motorcycles

How to move, and not mash a Knurled Knob

Quite often the adjustment screws on motorcycles that have a knurled knob for finger adjusting, become extremely hard to turn, Often exposed to the elements or fuel, grit etc. they are usually fine threaded and bear against spring pressure, compounding the tension.
To save mashing the knob with pliers, vice grips or jaw levers, use an appropriate sized socket or ring spanner with multi facet edges.

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1 Answer

clutch cable needs adjusted when i put it in gear it lurches forward when leaver is pull all the way back

There should be a knurled knob on the clutch cable that should give you an adjustment opportunity depending on model and year. If so, try turning it to see if it gets better or worse, if worse then turn in opposite direction.

Nov 26, 2015 | Motorcycles

1 Answer

85 yamaha 700

Yamaha don't make hard drives. But, I also fix motorbikes- the adjuster you are looking for is in the center of the carbs and has a knurled knob on it. (It looks like a wobbly mushroom and points towards the rear wheel and a little downwards.)

Jul 10, 2013 | Motorcycles

1 Answer

need help tweeking gears please

What's going wrong with the gears? Is it a new bike? I'll take a couple shots in the dark: Both the front and back derailers have adjustment screws (usually two). These are only limiter screws and they set how far out and in the derailer can travel. If your chain is slipping off either the biggest or the smallest gear then you may need to adjust these. More often, especially on a new bike, the cable worked initially but has since stretched slightly. This will feel more like many, if not all, of the gears want to slip to the next gear when you put power to the pedal. To fix this, look at either end of the cable housing (plastic part) for a knurled adjustment. Screw this "out" so that it extends the housing. Often this adjustment is up near the shifter lever/knob/etc and can be adjusted as you ride (of course watch for traffic). Fine tune this knob till the gears shift easily and stay when peddling hard. Try screwing one way, then the other till things improve. Good luck!

Aug 16, 2011 | Cycling

1 Answer

I'm helping my son-in-law fix a 1981 Z250. How do you adjust the clutch? It seems a bit wishy-washy!

It's only a 250 so it'll feel light to the touch. On the handlebar lever there is a cable attached with a slotted knurled nut, this can be adjusted to add about 1/8th free place before some tension is felt. If not tension is felt and the lever just flops then the clutch is way out of adjustment tighten it up,
Normally this Knurled nut (it's actually a round grooved nut you twist or screw using your fingers) has a full adjustment range from the lever to completely unscrewed of about 1.25 inches

Adjust the "free play" to about an 1/8th as explained if this doesn't help then internal clutch work is needed and best left to those that work with motorcycle and not a novice.

May 03, 2011 | 1981 kawasaki Z 250 C

1 Answer

Wheres the idle adjustment screw on my carb.. i have a 87 fz 600

There is a small knurled knob to the rear base at centre of carbies, this turns a worm screw, actuating a bar for all 4 carbs. The site below provides an exploded view and name of carby parts.

Here's a tip...if the knurled knob (designed to turn by hand) is too hard to turn, a multi facet (not hexagon facet) socket or ring spanner is far easier than pliers or grippers.



May 12, 2010 | Motorcycles

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