raphaeltube
Race Dog
- Joined
- Jan 12, 2015
- Messages
- 519
- Reaction score
- 10
- Location
- Cape Town, Western Cape
- Bike
- Yamaha XT 660 Z
Hi
If you hear a distinct & loud "ticking" noise coming from the front of your engine, get the cylander head taken off & the valve seats checked. -you could avoid having to re-bore/re-sleeve the cylander & Replace the piston & valve.
Only after this happened to me did I hear of 2 others with the same sad story.
The actual cause seems to be overheating.
The way my bike was set up when I got it was with an aftermarket exhaust & airfilter, but original jetting, which would cause it to run a bit lean (and a bit hot). These engines have dificulty dealing with any more heat than they were designed to handle.
I did get the jetting done & put the original exhaust back, but by that stage it was already making the ticking noise.
The only symptom/early warning is the ticking sound. -Performance seems unaffected.
The noise is from the valve seat having come loose, and riding up & down with the valve.
It's loud, high-pitched & in sync with the engine firing. (similar to if someone was tapping the engine with a small hammer every time it fires).
For me, the noise came and went a few times. -abruptly. it's either there or it's not.
I guess it goes away when the valve seat jams back in place for a while.
I actually took mine in and asked about the noise (although the mechanic could only go by my description as it wouldn't make the noise in the shop), and I was told it was probably a faulty auto-decompressor and nothing to worry about, and that he didn't think it would be worth the labour to open the cylander head & check it out.
Well if it happens to you, I assure you it's worth it.
Get the head opened & get the valve seat checked.
If not, you'll most likely need a rebore & a new piston a few hundred km later.
I remember taking a video with my phone of the noise, I'll see if I can dig it up.
-R
If you hear a distinct & loud "ticking" noise coming from the front of your engine, get the cylander head taken off & the valve seats checked. -you could avoid having to re-bore/re-sleeve the cylander & Replace the piston & valve.
Only after this happened to me did I hear of 2 others with the same sad story.
The actual cause seems to be overheating.
The way my bike was set up when I got it was with an aftermarket exhaust & airfilter, but original jetting, which would cause it to run a bit lean (and a bit hot). These engines have dificulty dealing with any more heat than they were designed to handle.
I did get the jetting done & put the original exhaust back, but by that stage it was already making the ticking noise.
The only symptom/early warning is the ticking sound. -Performance seems unaffected.
The noise is from the valve seat having come loose, and riding up & down with the valve.
It's loud, high-pitched & in sync with the engine firing. (similar to if someone was tapping the engine with a small hammer every time it fires).
For me, the noise came and went a few times. -abruptly. it's either there or it's not.
I guess it goes away when the valve seat jams back in place for a while.
I actually took mine in and asked about the noise (although the mechanic could only go by my description as it wouldn't make the noise in the shop), and I was told it was probably a faulty auto-decompressor and nothing to worry about, and that he didn't think it would be worth the labour to open the cylander head & check it out.
Well if it happens to you, I assure you it's worth it.
Get the head opened & get the valve seat checked.
If not, you'll most likely need a rebore & a new piston a few hundred km later.
I remember taking a video with my phone of the noise, I'll see if I can dig it up.
-R
