An expert who has achieved level 3 by getting 1000 points
An expert that got 10 achievements.
An expert that got 5 achievements.
An expert whose answer got voted for 500 times.
Re: Honda CRF 100 timing
Turn the motor over clockwise until the punch mark on the gear lines up with the arrow mark on the side case. Check to be sure that the cam lobes are facing to the rear of the bike, if they are pointing toward the front keep going until they face back and the punch mark aligns up with the mark on the case.
Check the cam gear to make sure the two marks on the gear are level with the surface of the head.
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need. goodluck!
- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
there is a method but you will have to have an understanding of valve timing
in an engine regardless of number of pistons when number 1 piston is TDC not firing, then the exhaust valve will be open and ready to close and the inlet valve will be closed and ready to open
so bring the piston up and near tdc
as you approach tdc you will see the exhaust start to close and at the same time the inlet valve will start to open
if you rock the crank back and forward slightly at tdc you will see that the valves are rocking
this is valve rock and indicates the cam is in time with the crank
it is only necessary to do it with no 1 piston
It doesn't matter how many cam shafts ( one cam shaft can be inlet valves only and the other can be exhaust valves only) there are, it is the exhaust and inlet valves for no 1 piston that you are looking at
how do you get tdc-- remove a plug and with a piece of wire place the end on the piston crown and as the piston comes up the wire will be pushed out as you rock the piston the wire will move in and out and the point before movement is tdc
probably as clear as mud unless you are engine savvy
Ok i got a 91 Legend. The repair manual says to lock the two cams in TDC. So find the blue driver side and red passenger side timing marks on the sprockets facing towards front. Thers a notch yellow lineat about 11 o'clock on the driver side and 1 o'clock on the passenger. line them up and find something to keep them in place. If they move you could have a valve bent by a cylinder so dont force it to much. When moving the sprockets you need to have the crank/oil pump gasket/harmonic balance r pointing up. theres a small arrow on the engine if you have your timing covers off that you line up with a little dimple tiny mak( you might have to remove the crank pully and behind it is the timing pully its half the size of the sprokets and rotates twice for every sproket thet turn. so make sure you keep thing fastened so you can save a lil time. line up the marks on the crank. not totaly sure but i think the front passenger side cylinder is the #1. Just start on the crank then by the tensioner, then driver or left cam, then whater pump then finally the passenger side cam. this one tends to move then when you try and TDC it swing with spring lifter or valve action. Move the passenger cam one tooth advanced clock wise. Clock wise is how a legend engine shoul be turned. If you dont advance the passenger cam a tooth the timing will most likly be one tooth off. This a little trick to put on perfect timing. After you turne the crak six times making sure on every turn that TDC marks line up, if not start over. when all is good you turn the crank nine teeth clock wise. every thing like the timing cover should be on now. locate the marks or three noches they should line up to a blue line on the crank pully. Oh i forget you can take the spark plugs out to help turn the the engine. oh you could also use an air compressor in the spark plugs to lift a valve or something if it falls on a piston. You will need 19mm socket a ether home made tool or the holder tool( ebay $25) or ( home depo 11/2 galvined pipe with hexagon shape $12.50). Alsow a 10mm, 5/16 or actually 8mm and 12mm. Thats all of the top of my head. Well i just did it few days ago. Good luck and if you have the time and the tools of confidence save your self a few weeks pay but if something aint right stop recheck or you might need to losen the rocker arms in the engine their 8mm and six up in there and keep the screews on lose lift entire rocker assembly. two turns at a time on every bolt till there all lose fift as unit be care full or it can fall a part in few dozen pieces. This may only need to be done if you have something hitting and the air wont put it in place. Peace
Set the piston to TDC (top dead center) this is the higest point the
piston will rise before moving on to the down stroke, either by lining
up the marks on the crank rotor or a long screw driver (large handle so
it wont fall in) down the plug hole and watch for the highest point lock
or hold at this point. If cam sprocket has marks line them with the cylinder head surface (sometimes the sprocket bolts) parallel. The cams should be fitted next on the
'compression' stroke meaing the all valves should be closed when the
cams are seated (no valves being pressed by cams) generally at this
point the cam lobs face away from the valves , next stroke down (ignition
of fuel) valves should be closed with the exhaust cam moving round
ready to rock on to the exhaust valve as the piston rises to the top
again (4th stroke exhaust) as the exhaust valve lobe rocks off the
intake cam lobe should be starting to rock on opening the intake valve
on the down stroke of the pistion. Trun the engine over by hand to make sure no valves are knocking the piston. Should be as follows 1.
all valve clearance free/rocking at ' TDC 1st 'down' stroke (ignition
of fuel) valves closed exhaust moving round but not pressing valve , 2.
2nd stroke 'up' exhaust valve rocking open and closing as piston tops
with the intake ready to rock on as the exhaust closes and piston tops
(exhaust), 3.3rd stroke 'down' (intake of fuel) as the piston moves down the intake valve should be opening. 4.
4th stroke 'up' compression of fuel all valves rocking closed as the
piston rises for the compression stroke back to TDC all valves
Intake, compression , ignition and exhaust. (**** squeeze bang blow)
On almost ALL Chevrolets Timing Marks are the Top Gear is your Cam Sproket,The DOT on the Casting goes straight Down at 6-a Clock, Then your Crank Shaft Sproket Goes Straight up at 12 A Clock. So the Dots are Meeting Each Other. This Will be TDC Top Dead Center.
Hi, to set the timing you should turn the No.1 piston to TDC, then turn the cam to where both valves on No.1 are close. The timing mark on the sproket should now be in line with the mark on the cilinder head. With No. 1 still on TDC fit the chain. After fitting turn the engin a few times by hand to make sure there's not a valve pushing against a piston.
tdc the piston and on the cam sproket thers a 0 on it aline this with the notch on the head that faces forward place the sproket with the 0 facking this mark then bolt up then replace the cam tensioner
To set the timing you should turn the No.1 piston to TDC, then turn the cam to where both valves on No.1 are close. The timing mark on the sproket should now be in line with the mark on the cilinder head. With No. 1 still on TDC fit the chain.
After fitting turn the engin a few times by hand to make sure there's not a valve pushing against a piston.
Bring the crank to TDC while WATCHING CAREFULLY the camshaft, making SURE that the pistons are moving in the correct sequence as the valve train. Once you have the #1 piston on TDC, Set up your valve train with what looks to be the most logical position. Then and only then should you consider the factory spec for setting the lead/lag time of the valve train, in degrees. Hope this helps....accordianman