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Gareth123
3rd February 2009, 19:18
Tappets? is that spelled correctly? I have a new old honda GL145 which needs its tappets adjusted. I know where they are, just not how to do it. How do you know when you have them correct?

Also if anyone knows what the correct settings are for the tappets on the gl please let me know, it will save a lot of guess work for my father(God bless parents who like to tinker on their sons crapped out bike) and I.

Also please enlighten me on what the tappets actually do to help the bike run better.

Cheers all

Magua
3rd February 2009, 20:05
I'm assuming you mean valve clearances when you say tappets.

What you're doing is adjusting the distance between the rocker arm (the thing that pushes on the valves) and the valve stem. If the clearance is too small between them (or non existant) then the valves may not fully retract from the engine, burning them. If the gap is too great, then you're wearing out your valve stem by constantly bashing on it.

In order to change them all you need toolwise (bar the tools needed to get access to them) are a ring spanner, a screw driver (probably a flat head) and some feeler gauges (you can pick these up at repco/supercheap) to measure the gap between the rocker arm and the top of the valve stem.

You'll know when the clearances are correct by the amount of resistance you feel when sliding the feeler gauge through. You should be able to slide it inbetween the top of the valve stem and the rockerarm with a "slight resistance" (according to my clymer manual).

hmmmnz
3rd February 2009, 21:48
valve clearances is bloody easy to do on a bike with tappets and lock nuts,
15min job (more if its ya first time)
there will be a timing mark on your flywheel, but you can just turn the engine over by hand untill the weight comes of both valve stems and then measure the gap, it should be about .1 to .15 mm clearance, bike depentant of course.
have fun, and make sure you do the lock nut up tight
you don't want this happening
http://www.kiwibiker.co.nz/forums/picture.php?albumid=1399&pictureid=15083

motorbyclist
4th February 2009, 10:42
google the clearances to be sure. the motor is basically the same as the XR and XL range from honda if that helps.

magua got the maintenance reasons right. you will need a twenty-something socket to get the covers off the rocker cover, an 8 mm spanner and a flathead screwdriver. might pay to remove the tank for better access, and yes the chassis will get in your way when doing the inlet side.

performance wise, too tight and the valves wont close. this costs you compression and bike will run poorly, too loose and the valves are closed when they should be open, costing you valuable ponies


enjoy the GL145 mate, they're great bikes and make good bucket racers :D

Gareth123
4th February 2009, 12:55
you don't want this happening
http://www.kiwibiker.co.nz/forums/picture.php?albumid=1399&pictureid=15083

I have no idea what i'm looking at in this picture. Someone will have to explain it to me.

Thanks guys for the info. I'm off to google right now

testastretta
4th February 2009, 19:16
It is a broken rocker arm.The piece between his thumb and forefinger is the adjuster which was most likely set to close and the pressure when the valve was opened was too much then...snap!The other end of the rocker arm is the cam follower.