Wednesday, September 10, 2003
Do-it-yourself tappet adjustment...
at this link containing contributions from the Madras Bulls:
"Tappet Adjustment - Cold
It is very essential to ensure that the valves are closed fully during the closing period of the cam. The tappet clearance should be adjusted properly to achieve this and to cater for a certain amount of thermal expansion of the working components. We recommend 'NIL' clearance of the tappets to be set at cold. Provision for adjustment is given at the bottom end of the push rod which sits over the tappet. Access to this is by removing the tappet cover.
Proceed as follows for adjustments. Bring piston to TDC at the end of compression stroke, so that both the valves are at the closed position. This may be ensured by seeing the valve timing marks if the timing cover is open, or through ammeter needle movement, when ignition is switched on.
Check the push rods. They must rotate thumb free without any up and down play.
In case the push rods do not rotate freely or if up and down play is noticed, the push rods need to be adjusted.
Loosen the lock nut in the adjuster, by holding the top nut. Thread in or out the bottom adjuster, till the correct push rod freedom is achieved. Retighten the lock nut after adjustments are complete.
CAUTION: If the cylinder head has been disturbed for any attention, ensure proper fitment of valve stem caps and rocker bearings before proceeding to tappet adjustment.
NOTE: Owing to the initial bedding down of the wearing surfaces, the tappets on new engines may require adjustment after the first few hundred kilometers."
And here's another technique from Dan at DRS Cycle. This is a cold engine adjustment, which avoids the over-adjustment and burnt valves that can occur with the engine warm:
"This is a repetitive task that needs to be done periodically. So
you need to get the hang of it! I have devised a system that makes
it very easy rather than very hard. First of all, do this on a
stone cold engine! Remove the tappet cover, push the kickstart
lever observing the intake pushrod. It will go up and then down and
you should then feel compression resistance with the kickstart
lever. I then put my thumb on the pushrod and feel/rotate it,
while I advance the kickstarter to top dead center. At this point, I
check to see if I can turn the pushrod. If it is tight at this
point I leave it, if it is totally free I tighten it to tight. The
trick I am sharing is to over tighten the adjuster and then snug up
the lock nut. I then turn the adjuster into the jam nut until I
have obtained the proper adjustment. I adjust the intake pushrod so
it has a heavy drag on it. I then repeat the process of adjusting
the exhaust pushrod in the same manner.
I adjust the exhaust so it has a light drag on it. I would mention
at this time, it is better to have a loose pushrod than an
overtightened one! So having said that, I do not like pushrod noise
at least when it is excessive. I repeat this process again, only
this time I watch the pushrod go up and down and I check it several
times to find if it has a loose spot. If I find a loose spot I
readjust, I always check each pushrod at least three times! The
manual says zero lash, do not forget to lock the lock nut! Nail it
but do not twist it off!"
at this link containing contributions from the Madras Bulls:
"Tappet Adjustment - Cold
It is very essential to ensure that the valves are closed fully during the closing period of the cam. The tappet clearance should be adjusted properly to achieve this and to cater for a certain amount of thermal expansion of the working components. We recommend 'NIL' clearance of the tappets to be set at cold. Provision for adjustment is given at the bottom end of the push rod which sits over the tappet. Access to this is by removing the tappet cover.
Proceed as follows for adjustments. Bring piston to TDC at the end of compression stroke, so that both the valves are at the closed position. This may be ensured by seeing the valve timing marks if the timing cover is open, or through ammeter needle movement, when ignition is switched on.
Check the push rods. They must rotate thumb free without any up and down play.
In case the push rods do not rotate freely or if up and down play is noticed, the push rods need to be adjusted.
Loosen the lock nut in the adjuster, by holding the top nut. Thread in or out the bottom adjuster, till the correct push rod freedom is achieved. Retighten the lock nut after adjustments are complete.
CAUTION: If the cylinder head has been disturbed for any attention, ensure proper fitment of valve stem caps and rocker bearings before proceeding to tappet adjustment.
NOTE: Owing to the initial bedding down of the wearing surfaces, the tappets on new engines may require adjustment after the first few hundred kilometers."
And here's another technique from Dan at DRS Cycle. This is a cold engine adjustment, which avoids the over-adjustment and burnt valves that can occur with the engine warm:
"This is a repetitive task that needs to be done periodically. So
you need to get the hang of it! I have devised a system that makes
it very easy rather than very hard. First of all, do this on a
stone cold engine! Remove the tappet cover, push the kickstart
lever observing the intake pushrod. It will go up and then down and
you should then feel compression resistance with the kickstart
lever. I then put my thumb on the pushrod and feel/rotate it,
while I advance the kickstarter to top dead center. At this point, I
check to see if I can turn the pushrod. If it is tight at this
point I leave it, if it is totally free I tighten it to tight. The
trick I am sharing is to over tighten the adjuster and then snug up
the lock nut. I then turn the adjuster into the jam nut until I
have obtained the proper adjustment. I adjust the intake pushrod so
it has a heavy drag on it. I then repeat the process of adjusting
the exhaust pushrod in the same manner.
I adjust the exhaust so it has a light drag on it. I would mention
at this time, it is better to have a loose pushrod than an
overtightened one! So having said that, I do not like pushrod noise
at least when it is excessive. I repeat this process again, only
this time I watch the pushrod go up and down and I check it several
times to find if it has a loose spot. If I find a loose spot I
readjust, I always check each pushrod at least three times! The
manual says zero lash, do not forget to lock the lock nut! Nail it
but do not twist it off!"
Sunday, September 07, 2003
Yesterday, the Royal Enfields (Madras Bulls) rode to the Ford India manufacturing plant...
and we had 9 bikes with a pillion or two (impressive turnout for a sometimes soporific set of cycle saps). Bulls came, saw & conquered. We can now probably assemble Ford Ikons due to TourMaster Nish's Ford plant knowledge (which he protects with a helmet). We had a lot of exercise (walking about the plant), but we ate better than I do at Tidel Park, played some carnival games (won some prizes), got a tat of some "monster" put below my iguana tat, saw some young teenage boys gyrating up on stage with really darling costumes, and planted an additional helmet "bug" in the Ford Managing Director's ear (just before he took a helmetless Bull-ride). There were no breakdowns today (other than hypocrisy). During our ride, of course, there were the omnipresent tea-stops. Here is where I have an issue (like it's my only "issue"): Is there a problem with a Bulls beer stop on a warm Saturday afternoon? Does one 650ml Kingfisher put a 90kg body over the BAC limit? It doesn't in my native ;^)
and we had 9 bikes with a pillion or two (impressive turnout for a sometimes soporific set of cycle saps). Bulls came, saw & conquered. We can now probably assemble Ford Ikons due to TourMaster Nish's Ford plant knowledge (which he protects with a helmet). We had a lot of exercise (walking about the plant), but we ate better than I do at Tidel Park, played some carnival games (won some prizes), got a tat of some "monster" put below my iguana tat, saw some young teenage boys gyrating up on stage with really darling costumes, and planted an additional helmet "bug" in the Ford Managing Director's ear (just before he took a helmetless Bull-ride). There were no breakdowns today (other than hypocrisy). During our ride, of course, there were the omnipresent tea-stops. Here is where I have an issue (like it's my only "issue"): Is there a problem with a Bulls beer stop on a warm Saturday afternoon? Does one 650ml Kingfisher put a 90kg body over the BAC limit? It doesn't in my native ;^)
