Yam_Tech314's official build thread

[Raymond]

Looking at that rocker shaft, there might be enough wear to justify replacement. And fully agree with Jim's point at #858.

Is the visible scoring something I should even worry about? Not needing new shafts will save me some change. . . Seems to me that the wear marks could just be the surface that the rocker rides on.

But to answer your general question, visible marks are not enough to justify replacing a part. The technical answer would be to measure accurately and see whether it's within limits. The practical answer is can you feel anything when you rub a finger nail along the surface? If not, what you see is usually just surface rubbing and not enough to worry about. My 2C.

 

[Bewarethemoon]

11 bucks shipped. You'd want to verify it's the correct P/N, but that's pretty cheap for NOS.
There's a lot of 'em on Ebay.... pretty reasonably priced.

If the seller had all four of these I would be purchasing myself.

 

[Bewarethemoon]

Looking at that rocker shaft, there might be enough wear to justify replacement. And fully agree with Jim's point at #858.

But to answer your general question, visible marks are not enough to justify replacing a part. The technical answer would be to measure accurately and see whether it's within limits. The practical answer is can you feel anything when you rub a finger nail along the surface? If not, what you see is usually just surface rubbing and not enough to worry about. My 2C.

ot sure I’ve seen the acceptable tolerances ever mentioned for these parts? That said I’m only referencing my Clymer manual, not checked my Haynes manual in a while.

 

[G_YamTech_314]

Ordered rocker shafts, valve springs, piston rings, a spring compressor tool, a cam chain rivet tool, and a clutch basket clamp tool! A total of $297

Money doesn't go too far these days.

The waiting game begins.

 

[Bewarethemoon]

Ordered rocker shafts, valve springs, piston rings, a spring compressor tool, a cam chain rivet tool, and a clutch basket clamp tool! A total of $297

Money doesn't go too far these days.

The waiting game begins.

Did you get the NOS rocker shafts?

 

[G_YamTech_314]

I didn't .. I found everything I needed in the same place, so I figured I'd save on shipping with keeping it to one order.

 

[Bewarethemoon]

What’s the finish quality compare like versus OEM on something like rocker shafts, I assume it’s a Mikes XS/XS Performance product?

 

[G_YamTech_314]

I am assuming the supplier is the same, I got everything I needed here: https://yamahaxs650.com/

They were $6 per.

Oddly, the rocker shafts are sold 2 per pack for $12. Or at least, that's how I understood it. If I get 4 for $24 I'm calling it a good deal.

I spent $25 per piston for ring sets,

$72.40 for valve spring set (dime city cycles wanted $102 for what looks like the same thing... I believe Dime City and mike's XS sources from the same supplier, so perhaps the link above is different. Hopefully cheaper doesn't mean CHEAPER... If you know what I mean.)

The rest of the money came from tools I got from their website as well but I'm running out of time on my break to enter in all that info... I'll do a comparison to the old parts and take some notes when they arrive to give you more info on similarities/measurements/patent loopholes when I can.

 

[G_YamTech_314]

I received the shipment of parts today!

4 rocker arm shafts.
4 inner and outer valve springs.
4 rocker shaft plugs and o-rings
2 piston ring sets.

I'll be measuring all parts for comparison purposes, to hopefully help you all in deciding whether the price is right for some of the parts. If the quality exceeds expectation, you'll know where to go for your next parts run.

I also got a clutch basket clamp, a valve spring compressor (that already seems decent) and a rivet tool for different types of chains including drive chains!

Pictures will come with the data when I go out and grab some stuff I need!!

Stay tuned!

 

[TwoManyXS1Bs]

Mid-term test.

If the valve springs are progressive, which end goes up...?

 

[G_YamTech_314]

Mid-term test.

If the valve springs are progressive, which end goes up...?

I'll get back to you on that... I took a nap, and my manual is on the dining room table at the moment.

Wild guess: the tighter part of the coils faces the motor(?)

 

[G_YamTech_314]

I was incorrect a out it being in my manual... I don't know where I read that info (probably on here)

Which way is correct? Also, the manual DOES mention left hand/right hand winding direction.

Outer is right hand, inner is left hand. That's all I got. I'll stick with my previous guess. Lol. Correct me if I'm wrong. (Please!)

 

[Jim]

Here's a question that ain't in the book... why 2 spring per valve? Why not just 1 strong (enough) one?

 

[TwoManyXS1Bs]

Or a beehive spring?

 

[TwoManyXS1Bs]

Here's a hint...

http://www.xs650.com/media/70-07-01-s237-01-heavydutyvalvesprings.18844/

 

[G_YamTech_314]

Here's a question that ain't in the book... why 2 spring per valve? Why not just 1 strong (enough) one?

Push/pull and keeping the valve straight in the guide? I'll read the link below just after this post. I just enjoy guessing and thinking stuff through before giving in and finding the answer.

 

[G_YamTech_314]

Or a beehive spring?

I'm honestly unfamiliar with this... I'll look it up and do a learnin!

Here's a hint...

http://www.xs650.com/media/70-07-01-s237-01-heavydutyvalvesprings.18844/

Interesting. I can tell you with full confidence prior to even measuring that the new outer springs are AT LEAST a mm longer than the old outer ones. They're noticably heavier too. I no longer doubt the need for new ones. I'll be grabbing a few things from the auto parts here in a few minutes, then I'm off to measure everything and post the data for you all to meddle with. The new springs will surely help with rpms.

The inner springs seem to be the same length from a side by side view, another interesting first look observation is that the windings are further apart on the new outer springs by a lot.

I did see them labeled as "performance valve springs" but the description said they could replace stock springs so I figured nothing but improvement would come from it. (I hope)

 

[G_YamTech_314]

I tried to do this in a way that would limit my amount of typing.

The pics mostly speak to the differences in the specs and patent differences.

Hope this helps.

Cam chain rivet tool

Piston Ring Sets

Clutch basket clamp tool

Valve spring compressor.

This tool does require some 'splainin. It seems to have some adjustable bits to it. While it seems cheaply made, it has two acorn nuts that come off, this is cool for the exhaust valve portion because the threaded rod is flat on the end. No more anxiety when putting the round tool end on the flat valve surface and clenching hoping it doesn't slip.

It also makes it so you can disassemble the tool for any reason...

The other side of the tool where you install the valve keepers has another adjustable collar on it. The whole outside edge of the compressor is threaded, allowing the collar to come down for what I assume would be used to ensure no slipping, or for bigger spring collars, not really sure. Maybe this is common, I'm still excited about it though.

Old valve springs and their measured length

New valve springs and their measured length. Note the difference.

Outer springs are 1.87mm longer with one less coil in total

Inner springs are only 0.49mm longer with TWO less coils total. Perhaps this was the difference in "progressive" vs "regular" valve springs? I'm not sure.

The new springs also seem to lack a prominent "tight spot" the coils seem even in distance all around, but noticably stiffer. How do I determine which direction to install them... Interesting.

Old rocker shaft (I only measured one of each, old and new)

New rocker shaft. A total of 0.11mm longer in length. The only other noticeable difference will be pictured below. Probably to avoid patent confliction, the inner groove is different than the old shafts, but I think it will do the trick no problem!

The new one has a more prominent chamfer on the inner groove.


Finally, the biggest difference I found was in the new collars. The shoulder height for the inner spring is MUCH taller than the old collars. The specific difference measures 1.58mm. The New collar is wider on the inner spring height by what I consider a big difference.

Excuse the poor drawings, but you can see it clearly in the picture I took as well.

That's all the information I have for you guys tonight. I hope it helps to see what the quality is of the site I purchased all of this from!

If you do like what you see the link is here:
https://yamahaxs650.com/

 

[Jim]

Push/pull and keeping the valve straight in the guide? I'll read the link below just after this post. I just enjoy guessing and thinking stuff through before giving in and finding the answer.

Here's a hint. All things in the universe have a natural frequency.

 

[G_YamTech_314]

Here's a hint. All things in the universe have a natural frequency.

Upon doing more independent research, two springs of the same thickness have an advantage over one heavier spring because it allows for more valve lift without risking coil binding. It also eliminates the need for a stronger (usually more brittle) material spring.