Loosen valves on a Honda?

**STiForester** · 01-02-2012, 11:10 AM

Has anyone ever heard of loosening the valves on a Honda 4 stroke because it runs better? Sounds crazy to me

**fabiodriven** · 01-02-2012, 11:13 AM

There is a certain amount of lash they should have. Check the service manual for the respective machine. That's how they'll run best.

**jmax857** · 01-02-2012, 11:35 AM

It will only run better if they were too tight. Its pretty ssimple to set them, they could alsoo be too loose. Lots of times if your valve adjustment is out of whack you will notice a big difeerence in how easier it starts after setting them.youu should get a manual and give it a try, its a good part of routine maintenance to set them. Especially on a honda, after you do it a few times it shouldn't take you long. All you do is undo the timing plug oon the crankcase above the flywheel, line it up with TDC, unscrew the timing covers, and set the lash with the jam nut and setscrew. You will need a Manual for the settings, it will explain how to do it aswell. If you've never done it, give it a try, there's no way it will make it run worse.

**twitch101** · 01-02-2012, 12:13 PM

actually, you can make it run worse if you have trouble finding TDC like i did with my 350x that has an F and I. not sure why. as long as you get it on tdc youll be good though. ive heard of guys adjusting valves while an engine is running on a car. WITHOUT using feeler guages! strictly by sound. i wouldnt trust it.

**fabiodriven** · 01-02-2012, 12:18 PM

Originally Posted by twitch101

ive heard of guys adjusting valves while an engine is running on a car. WITHOUT using feeler guages! strictly by sound. i wouldnt trust it.

That's actually not unheard of for cars. I've seen people do it with small block Chevys. If you know what you're doing it works just fine, on cars that is. I wouldn't do it on a trike.

**EarlyBronocGuy** · 01-02-2012, 08:00 PM

Originally Posted by twitch101

actually, you can make it run worse if you have trouble finding TDC like i did with my 350x that has an F and I. not sure why. as long as you get it on tdc youll be good though. ive heard of guys adjusting valves while an engine is running on a car. WITHOUT using feeler guages! strictly by sound. i wouldnt trust it.

I've done that myself, on the 350 (hydraulic lifters) in my '72 Chevelle. Removed the valve covers, put clips over the pushrod ends of the rocker arms (to keep oil from spraying everywhere), started the engine and let it warm up, then backed off the pivot stud nut of each rocker arm (one at a time) until the clearance opened up between the valve tip and the end of the rocker arm and it started "clicking", then tightened the nut until it just stopped.

Can't do that on a trike, the adjuster is on the end of the rocker arm and would be moving up and down rapidly while the engine is running.

**STiForester** · 01-02-2012, 08:05 PM

Hmm thanks. I just picked up a 250sx. 1985. Starts up first kick even cold. Everything works great. Drive 7 hours which sucked. I want to do the gear oil in the rear. Motor oil and adjust the valves. This will be the first 4 stroke I've ever worked on.

**atc007** · 01-02-2012, 08:08 PM

Originally Posted by jmax857

It will only run better if they were too tight. Its pretty ssimple to set them, they could alsoo be too loose. Lots of times if your valve adjustment is out of whack you will notice a big difeerence in how easier it starts after setting them.youu should get a manual and give it a try, its a good part of routine maintenance to set them. Especially on a honda, after you do it a few times it shouldn't take you long. All you do is undo the timing plug oon the crankcase above the flywheel, line it up with TDC, unscrew the timing covers, and set the lash with the jam nut and setscrew. You will need a Manual for the settings, it will explain how to do it aswell. If you've never done it, give it a try, there's no way it will make it run worse.

This post is basically right,,,FOLLOWING THE MANUAL..However !!,,You can MAJORLY mess things up adjusting valves. Too tight, you will kill your rocker arms and camshaft. You can break valve tips. Also with loose valves,,the extra lash is hard on the valve tip,,and can break them. Especially on 350X exhaust valves. Seen that way too many times. You want your valves adjusted where they are supposed to be.

**JohnR.** · 01-02-2012, 08:28 PM

Usually if they're too tight (and no one has been monkeying around in there) its because the valve seat is starting to get pounded down allowing the valve to move further "up" and therefore the lash becomes too tight. I've seen it before and you can loosen the valves but if it keeps happening you're gonna need a valve job.

**STiForester** · 01-03-2012, 12:28 AM

Ok thanks. It runs great but I would clean the carb cuz it Boggs at wot

**STiForester** · 01-05-2012, 12:15 PM

New plug and fuel lines an fuel filter and it runs great. Air filter is next on my list. But my Tecate comes first cuz it's almost done

**STiForester** · 01-08-2012, 09:19 PM

How do I find tdc an be sure it's tdc on my bike. I want to adjust the valves but its my first time. The bike starts first kick even cold. I don't want to screw this up

**Headsup** · 01-08-2012, 09:41 PM

if it starts first kik in cold, the valves seem just fine. I wouldn't touch them.

**STiForester** · 01-08-2012, 10:02 PM

Ok good. Thought so but I like to do everything myself to make sure it's good. I want to dig into the carb and give it a thorough cleaning

**jmax857** · 01-08-2012, 11:00 PM

Get a manual, it will save your life.

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Loosen valves on a Honda?