How to lap valves (works on all 4 stroke engines)

This is a quick tutorial on how to lap your valves on pretty much any 4 stroke dirt bike, pit bike or carengine, simple and to the point, this is being done on a pit bike head..

[@MilanGilgames]

I love your camera angle. You got it perfectly. We can see everything. It was a really really good idea to place your camera where you did place it.

[@schoonbeek2]

Your comment is great

[@montane_west]

Thanks 🙏🏿

[@RawVeganFruitarian]

Needed to put both valves in when cutting the seat to avoid compound getting into the other valve shaft

[@montane_west]

Thanks for the tip, I'll definitely keep this in mind, don't want to ruin any valve seals or stems 😅... Thanks again 🙏🏿

[@Mike-cb7dv]

When you put the motor together can you please show how to adjust the valves

[@montane_west]

No problem 👍🏿

[@stumpedtree4204]

hey man. any videos on removing the valve from the head before seating it. and then re installation would be very helpful for me

[@montane_west]

I got you covered, I'm gonna be posting how tos very soon mainly for the minis 🤙🏿

[@tomomeara7488]

Outstanding video. love the drill idea. worked great.

[@montane_west]

Thank you 🙏🏿

[@jasperdomacena6491]

using the hand valve lapping tool is better since you rotate it in different directions, you can feel the grit fining out, it doesn't stress out the valve seat too much and it doesn't
the drill method is faster but it's prone to errors, but using the hand tool is forgiving but it takes a much longer time.

[@JasonBohl]

just as an FYI he stated that at the beginning of video.

[@christophermcmahon7920]

I use both.

[@therock231126]

He just told me that my KZ 1000 has low compression in cylinder one and four. So mechanic that’s why my engine is going bad cause of bad gas mileage now. A good friend on Facebook said to look at this video and this is probably what it is.

[@stumpedtree4204]

very possibly could be!

[@haydenmccarthy325]

could be could be piston and ring wear as well

[@montane_west]

Did you ever figure out the issue?

[@therock231126]

Nothing yet. Looking for a new mechanic to look at it. Guess I won’t find out until I open my engine or replace the engine. Some say it’s my rings that are going bad inside.

[@mtbridingog9083]

@@therock231126 is there any smoke on start up and while your riding ?

[@connorwilson8078]

Na bro just pour but oil in exhaust port and check to see if valve leaks, makes it easier to see

[@montane_west]

Thanks

[@starwarscrazy4540]

Do not lap valves i did and it destroyed my head on yz250f 2001. Titanium valves do not need to be lapped. Steel valves need lapping but you run the risk of destroying your head. Get new head valves ect install and ride. Remember steel is harder to grind than aluminum so your head will ware faster than steel valves.

[@montane_west]

I just read a similar comment and already messed around and found out 😅, steel uncoated are exceptional in most cases from my new knowledge 😁

[@ITzZMB]

My friend just got a 125cc and when in first gear it's screaming soon as he sets off ready for second gear literally basically setting off in second any idea

[@montane_west]

Make sure the choke is off

[@mattcero1]

Nice video. Have you considered alternating direction on the drill while lapping?

[@montane_west]

I do when I go back over with my hand as my last step

[@mattcero1]

@@montane_west I lapped the 4 valves on the right side and retimed them with that jig you get from BMW and all was well. Well enough to do 12 states and 11 national parks a few weeks after the job was done last summer. That cam locking jig was money well spent.

[@montane_west]

@@mattcero1 sheesh, I'd say you did one hell of a job on those valves 💪🏿💯🔥😸

[@oforilawson4010]

Please my valves and plug keeps damaging. What maybe the cause?

[@jtgross2324]

Timing?

[@jtgross2324]

Maybe base gasket is too thin, check squish

[@montane_west]

Could be a few things, maybe the rod bearing is shot, valves out of clearance/off timing, be piston could be too tall... There's a bunch tbh. Find out the position of contact 🙏🏿

[@Jd_aroneds_]

Diesel fuel I use to check valve sets

[@montane_west]

I'm learning lots about diesel currently 😁, you are a smart man 😉

[@MrTtillub]

Good video , Thank you sir.......

[@montane_west]

Thank you and your very welcome 😁

[@joseph-mariopelerin7028]

good luck making sure all that compound is out of this engine afterward...

[@montane_west]

It's definitely a process 😅

[@joseph-mariopelerin7028]

​@montane_west oh! I actually did it a few months back... worked like a charm... thanks for the tips 😀

[@omaraliahmed2013]

What is the brand of valves

[@montane_west]

There the oem ones that can stick in the motor it's a gpx140

[@mxthunder2]

I would not say this works on all 4 stroke motors. Many if not MOST 4 stroke valves have coating on the seats that will wear off if you lap them and cause the valve to wear out in a very short period of time. Read the service manuals. Most say NOT to lap valves at all. This is more relevant for lawn mower engines lol

[@montane_west]

I learned this the hard way lapping titanium values 😅, but thanks anyway 🙏🏿

[@schoonbeek2]

message incoming @ 5:30

[@montane_west]

😁🙏🏿🫡

[@omaraliahmed2013]

I hope you respond quickly

[@montane_west]

🥺

[@sumanmondalsuman7635]

Làp paste name

[@montane_west]

Permatex valve grinding compound

[@sumanmondalsuman7635]

Thanks brother 👍👍👍
India

[@JohnWick-hx7bc]

I dot think u should use a drill for this 😂

[@montane_west]

I think it is more valuable by hand, the drill is faster but you can mess things up just as fast as it spins 😬