200x. Bent valve (a brand new one dohhh)

[PAPA250r]

Ok so i rebuilt my 200x new cylinder 10.25:1 wiesco "new" valves ect ect

So got her running was breaking the motor in second ride. It took a crap and bent the exhaust valve.

Now my mistake was using a bootleg china valve which i wont do again .

question 1 - whats a good source for a GOOD reliable valve

Question 2- what usually causes a valve to bend ?

[leevarnado]

honda oem or kibble white valve.

[Scootertrash]

Question 2- what usually causes a valve to bend ?

Hitting the piston.

What happened when it crapped out?

[shortline10]

If the timing was set corrrect your bent valve was prob caused from timing chain slack .

[tri-Z ripper]

Or lack of retensioning of timing chain. First question, i haven't seen yet. Did you use a new timing chain?

[atc007]

Agreed ^^^ Timing chains should be replaced FAR more often than they are! They are highly overlooked. Just because the tensioner Will pull it tight,,does not mean it doesn't need replaced. Folks with newer 4 strokes come in knowing this. But us old dogs from way back had to learn as these machines get older : )

[wantit7898]

went and picked one up today guy had new rebuilt motor on it i got it out road it lost compression leaks wear top and bottom gasket go has low compression but wont start what do i do

[fabiodriven]

went and picked one up today guy had new rebuilt motor on it i got it out road it lost compression leaks wear top and bottom gasket go has low compression but wont start what do i do

OK new guy. This is no way to start out here.

First of all, you need to start your own thread with these questions. What you are doing is known as "hijacking" this poor guys thread.

Secondly, you need to work on the grammar. What you just wrote makes absolutely no sense. You're not texting with your buddies here, you're speaking to the authorities of all things trike. Please address us as such.

:welcome:

[PAPA250r]

Yes i did use a new timing chain . But my adjuster was loose so i guess thats the answer .

It just shut off and had no compression.



Thanks for the help .

[Dirtcrasher]

Either the keepers fell out (weren't in right from the get-go) or if it ran well, your timing chain slack did it. I wonder if you were off a tooth also.....

I agree, ALL of the 200X motors need 2 new guides and a new timing chain and it's under 100$ so do that too next time around...

[shortline10]

Yep I see it all the time LOL . Loose timing chain = bent valves . Just be glade you didnt do it on one of those new 5 valve high strung motors they have out today .



Yes i did use a new timing chain . But my adjuster was loose so i guess thats the answer .

It just shut off and had no compression.



Thanks for the help .

[PAPA250r]

Pretty bummed lol. Dont have a replacement valve and the engine was runnin mean before it happened . Used to my 200s. The clutch is much more fun

[oscarmayer]

your gonna have to repalce the valve, and before you do so. checkt he guide to ensure you did not crack it. it's not uncommon to crack or split the guide on a contact spot, also check the piston. make sure you did not damage it. a slight touch mark is one thing. a gouge is bad and time to replace it too. Yep, these can get expensive if you rush. always and remember to always take your time and tripple check everything before you ever try to run it.
after i rebuild a motor, i will kepe the plug out, keep the fuel off and spray some wd-40 down the hole and hole the throttle open and pull the rope or hit the starter for a while. I make sure i am getting oil to the top of the motor befor eI ever try to start a new engine. this ensures no grinding of metal to metal parts. Yes I use moly lube, but still i like to take extra precautions.

[Motorious]

question 1 - whats a good source for a GOOD reliable valve
I just bought a Vesrah exhaust valve for my 200X off ebay (original valve was burnt) for about $27 shipped. Not sure how they compare to OEM, but I do know Vesrah has a reputation for quality (well known for their gaskets anyway) and they are made in Japan if I'm not mistaken.

[PAPA250r]

your gonna have to repalce the valve, and before you do so. checkt he guide to ensure you did not crack it. it's not uncommon to crack or split the guide on a contact spot, also check the piston. make sure you did not damage it. a slight touch mark is one thing. a gouge is bad and time to replace it too. Yep, these can get expensive if you rush. always and remember to always take your time and tripple check everything before you ever try to run it.
after i rebuild a motor, i will kepe the plug out, keep the fuel off and spray some wd-40 down the hole and hole the throttle open and pull the rope or hit the starter for a while. I make sure i am getting oil to the top of the motor befor eI ever try to start a new engine. this ensures no grinding of metal to metal parts. Yes I use moly lube, but still i like to take extra precautions.


Thanks for the tip ill check the guide .. The piston is fine luckly . I will be getting an oem valve to replace it.

[tri again]

went and picked one up today guy had new rebuilt motor on it i got it out road it lost compression leaks wear top and bottom gasket go has low compression but wont start what do i do

hi and welcome

there are manuals in the 'world class help' section for free altho they don't always address real world issues.

You can try the search key too.
or start a new thread specific to your particular problem.

For THIS thread, I'd have to agree with the chain theory.
if they stretch, you'd think the valves would open later, but if they're set real close (opening at) to tdc they may kiss if the connecting rod expands when it gets warm.
Sloppy valve guides may let them rock or tip just enough to hit the piston depending on the clearance to start with.
The drive side of the chain, if stretched, seems like it would cause the valves to open later when the piston is already on the way down but backside slop, aka tensioner side, may allow the chain to jump a tooth on either the cam or crank sprocket..

What was the ol' chevy trick?
just put on old timing chain one tooth back to compensate for the wear and stretch.??

Valve keeper let go?
weak valve spring let the keeper fly out?
"cheap' valves can stretch over time and change the clearance between the valve and piston.
but that usually takes lots of heat and time and abusive overrevving.

Whatever it is, I hope it's an easy fix.

Just make sure you polish the 'dent' on top of the piston so it doesn't glow and cause pre ignition pinging.