23 Aug 2010

De-stressing your bike's engine

What would you do if your bike's pick up has reduced noticeably and the engine feels a little too stressed after it's just back from the mechanic's?  Sometimes mechanics tune things slightly wrong, and here are a couple of things you can try to fix the bike yourself:

Reduce the idle speed of the engine if it's too fast.  Recommended idle speed for your bike, how to change the idle speed, etc. vary for each bike.  For Honda Unicorn, the recommended idle speed is 1400 ± 100 rpm.  You can adjust the idle speed by adjusting the knob shown in the picture.  One thing to keep in mind while adjusting idle speed is that, you should ride the bike for 2 or 3 kilometers to warm the engine up before setting the idle speed.

Loosen the clutch cable if it's too tight.  But how do you know if the clutch is too tight?  A few symptoms I know of are:
  • The bike's pick up is slower than usual.
  • The engine stresses more than usual even at slow speeds.
  • When you have to use the clutch very frequently -- for example in stop-and-go traffic -- because the clutch is too tight your fingers become sore quicker.
You can loosen the clutch by adjusting the nut shown in the picture.  One good thing about this nut is that you don't need a spanner (or wrench) to adjust it; you can simply use your fingers.


  1. My bike stops as soon as i slow it on the breaker. It is 3 month old unicorn and it has run 2690km . what should i do so that it does not stop?

    1. See if your idle speed is not too slow? Also, using petrol from Bharat Petroleum made my engine run smoother. (This was all several years ago; I am not sure how well they apply to new Unicorns.)

  2. Thanks !! Idle rpm was a bit concern for me as my new uni 150 shows rpm of 1.1 when started which goes up to 1.9 after few km run. So now I have got the idea to set it after few km run..