Engine Rephase Rebuild Thread

[alfredo]

It's been a bit since I posted an update on this. Wanted to keep you guys in the loop. I have been extremely life busy, as usual, lately so working on this has fallen behind.

The bottom sump plate and the engine tear down guide that I found on here, printed and put into a folder for easy reference.

This is where you guys insert laughter: I put a little spec heater in front of my case for HOURS and got nothing. I tried and tried to split the case and couldn't get it done. Lots of tapping and heating with the space heater and still nothing. Ugh.

Giant plastic bin with bags and bags of parts. I have a bad habit of labeling the bejesus out of everything so I can have half a chance of getting it back together without extra parts. I have found that the "Dollar Tree" sells fake zip locks in all sizes for a $1/box. Perfect for this kind of use.

I went to Ace Hardware and got some propane torches. I have been meaning to get some for a while now, but now I really needed them. I got the suggestion from another forum member whom I can't remember the name of right now, but it worked. I used the torch all the way around the block where they were mated. Used a thin paint scraper to get into the groove and eventually . . . victory!

The crank in it's 360 degree vibratory goodness. Forgot to put the impact on the rotor so I left it and 'donated' it to Hugh. Hope he didn't mind donation (cough cough 'extra work'). Both the crank and the cam are on their way to Hugh via the USPS.

The cases mostly bare. Hoping to get out in the garage tomorrow or soon and get everything cleaned up.

Gears look pretty good as far as I can tell. No missing teeth or obvious marring other than the factory marks.

Really contemplating the 5th gear overdrive, but I am not sure if it's worth it or if just changing up the sprockets is the answer. I know I have broken it down all the way and now would be the time to do it, but it's more money and more taking stuff apart. Just not sure if it's really worth it and would love some advice.

Hoping to get all this wrapped up in the next couple of weeks so she can be road ready for the revenge run.

 

[Tim of DO THE TON]

Just watch out on the transmission shafts - there are two thin shims behind each of those smaller roller bearings that are loose on the shafts - i.e. they'll come off and can get lost. They may be stuck to a gear or the bearing with a film of oil.

Just saying it because I misplaced one of mine and am now waiting to reassemble.

Also for future reference (I learned the hard way) it's way easier to remove the sprocket while the engine is in one piece - you need to remove it to replace the seal behind it.

Also, I took the advice of some and ordered new OEM seals from Yamaha instead of using the MikesXS Parts Plus kit I already had in-hand. $80 for OEM vs $40 for Parts Plus and it turned out in my case anyhow the OEM Yamaha seals are identical in all ways to the Parts Plus - meaning they're made by the same factory, same markings, same branding on the seals.

 

[Tim of DO THE TON]

Oh, and while I haven't ridden mine yet, do the 5th gear change. Super easy to do now, and for $60 probably well worth it vs. spending more than that on sprockets which change your ratio in all gears, not just where it counts.

 

[KentMoney]

dude, it would be ridiculous not to do the 5th overdrive. it's such a simple and cheap investment, and you're after those comfortable cruises so it's essential IMO.

and I too was unable to change the seal behind the drive sprocket because I didn't remove it BEFORE i took the cases apart. next time I do a rebuild I will be removing the sprocket first thing so that I can change that seal out.

other than that, looks like you're making good progress alfredo. do the overdrive + gearing change for god's sake!

 

[Tim of DO THE TON]

Well you can remove the sprocket / change the seal after you take the transmission out - you can rest the two shafts back in the case, lock it up and take it off.

I got lucky and my sprocket nut spun off easily after flattening out the lock washer.

 

[the Norwegian]

Hi
As a newbie to rephasing i have to ask:
Do this job increase the hp and torque?
Or is it only to decrease the vibrations?

 

[pamcopete]

Just a note for engine assembly if you have a PAMCO. Some after market gaskets for the points and advance housing are thicker than OEM and will move the housings out too far causing the PAMCO rotor to contact the PC board screw.

Use only OEM gaskets or equivalent thickness gaskets for the points and advancer housing.

It's possible that thick gaskets could also cause advance rod binding as well in a points setup.

 

[glennpm]

Hi,

Where is the "engine tear down guide" filed that Alfredo mentions above? It doesn't seem to be in the tech section and my search failed. I did piece together some emails and used the manual to get mine apart but a better pictorial would be great.

 

[jefft]

What year engine is this your rebuilding? I know its stated that the 5th gear overdrive is for later models. Why wouldn't it work on a 77? Anyone tried it?
jefft

 

[pamcopete]

What year engine is this your rebuilding? I know its stated that the 5th gear overdrive is for later models. Why wouldn't it work on a 77? Anyone tried it?
jefft

Yamaha changed the shape of transmission gear teeth from 78 on and this is indicated by lines cut into the crest of each tooth. Perhaps if you installed the complete gear set from a later model it would work, but I do not know for certain.

 

[glennpm]

Okay, I found some good manual links. How does this get posted on the tech pages?

Thanks to 5Twins for the translated and excellent German manual!!

Part 1 starts on this page:

http://www.xs650.com/forum/showthread.php?t=3759&page=2

Also found this http://www.xs650.fi/pohja_files/cmm_9-11_2002_1.pdf

Increment the ... 2002_2, up to ... 2002_16 to get all the parts.

 

[Tim of DO THE TON]

Yamaha changed the shape of transmission gear teeth from 78 on and this is indicated by lines cut into the crest of each tooth. Perhaps if you installed the complete gear set from a later model it would work, but I do not know for certain.

MikesXS sells the mating gear for the other shaft, so I think you can install them both on an earlier year transmission.

Or spend the money on a later model transmission off eBay - they're plentiful and lots of Buy it Now's for $20-$30 for the complete set vs. $65 for the other 5th gear cog.

 

[alfredo]

MikesXS sells the mating gear for the other shaft, so I think you can install them both on an earlier year transmission.

Or spend the money on a later model transmission off eBay - they're plentiful and lots of Buy it Now's for $20-$30 for the complete set vs. $65 for the other 5th gear cog.

If you have a 78+ trans, you would not need the mating gear though. Just the new 5th; correct?

 

[Tim of DO THE TON]

That's my understanding and mine spins nicely with just the one gear instaled. MikesXS is a little unclear about it saying the other gear is required but I'm pretty sure that's if you have an earlier tranny.

 

[alfredo]

Just watch out on the transmission shafts - there are two thin shims behind each of those smaller roller bearings that are loose on the shafts - i.e. they'll come off and can get lost. They may be stuck to a gear or the bearing with a film of oil.

Just saying it because I misplaced one of mine and am now waiting to reassemble.

Also for future reference (I learned the hard way) it's way easier to remove the sprocket while the engine is in one piece - you need to remove it to replace the seal behind it.

Also, I took the advice of some and ordered new OEM seals from Yamaha instead of using the MikesXS Parts Plus kit I already had in-hand. $80 for OEM vs $40 for Parts Plus and it turned out in my case anyhow the OEM Yamaha seals are identical in all ways to the Parts Plus - meaning they're made by the same factory, same markings, same branding on the seals.

Might be a little too late. I can only find one of the shims you speak of (#29 here) on my bench. Is this the right thing you were talking about having two of? If so, where do I go to buy another ?

 

[Tim of DO THE TON]

No - there is only 1 #29 and from what I understand you position it so 1/2 of it is in the bottom case and 1/2 in the upper case.

It's #27 and #11 I'm talking about - same part numbers.

 

[alfredo]

No - there is only 1 #29 and from what I understand you position it so 1/2 of it is in the bottom case and 1/2 in the upper case.

It's #27 and #11 I'm talking about - same part numbers.

27 and 11 where? I looked at the link I sent and those are bearings and circlips. Not sure if I understood you.

 

[Tim of DO THE TON]

Look closer and read the parts list. They're shims - basically washers. They go between the bearing and a circlip in one instanc and the gear on the other shaft.

 

[alfredo]

So. Another update before the weekend starts.

I have gotten most everything apart and blasted. I cleaned the case halves at a local machine shop, but the cases were still stained pretty badly. So, I went and got some engine paint and primer and went for the aluminum look. After I got both halves painted completely my father showed up to inform me that I should have used outboard motor primer as it has some sort of additive (zinc I think) that helps the paint adhere 5x better. Oh well, if it chips it chips.

Here is a shot of the top of the motor blasted in my cabinet. Took a long time to clean out all the glass bead from the oil passages in the cover and the tappets. Man. I thought people were joking about the glass bead getting everywhere, but they were not.

Here are some pictures of it getting put back together. I checked the tappets for cracks and scratches as well as replaced the end caps (forgot to get a picture) with the aluminum ones from mikes.

Then finally, last weekend, I got a special present in the mail fairy and from someone who I am sure you all know: Hugh.

It was my camshaft and crank, rephased and golden. Also, a PMA kit. Really excited about this and everything came clean, make, tooled and covered. I checked the welds and had my father look closely and it's pretty spot on. One guess what I will be doing this weekend .

Wanted to get back with some of the commenters since I have been slacking for a while now:

Just a note for engine assembly if you have a PAMCO. Some after market gaskets for the points and advance housing are thicker than OEM and will move the housings out too far causing the PAMCO rotor to contact the PC board screw.

Use only OEM gaskets or equivalent thickness gaskets for the points and advancer housing.

It's possible that thick gaskets could also cause advance rod binding as well in a points setup.

Noted and thanks Pete. I will be scouring this forum when it comes time to install that Pamco kit for sure. Do you know if the Athena gaskets work? These are the paper ones from mikes.

dude, it would be ridiculous not to do the 5th overdrive. it's such a simple and cheap investment, and you're after those comfortable cruises so it's essential IMO.

and I too was unable to change the seal behind the drive sprocket because I didn't remove it BEFORE i took the cases apart. next time I do a rebuild I will be removing the sprocket first thing so that I can change that seal out.

other than that, looks like you're making good progress alfredo. do the overdrive + gearing change for god's sake!

I know I know. My gut was telling me to do it, but my wallet would cry. Anyhow, you talked me into it. I went ahead and pulled the trigger on the 5th gear. I just ordered the one from mikes since my trans has the marked teeth. Hugh has a tutorial on Biker Metric that I will be following this weekend for the 5th gear installation.

As for that seal, I am just hoping my impact wrench and some sort of jerry rigged clamp will be enough to pop that sprocket off.

Yamaha changed the shape of transmission gear teeth from 78 on and this is indicated by lines cut into the crest of each tooth. Perhaps if you installed the complete gear set from a later model it would work, but I do not know for certain.

On that 5th gear replacement biker metric tutorial I spoke of, hugh mentions that he is doing just what you said Pete. Using a set from an newer bike in the older case. So it should work.

 

[KentMoney]

good to hear man! Yes, the installation is very, very simple. Just make sure you have some circlip pliers. I got a set from a local auto shop for like $8! totally worth it.

So, I've been keeping an eye on my bike in terms of vibes, speed, and RPMs and here is the verdict. With a 277 rephase, 5th overdrive, and 17-32 gearing my highest sustainable cruising speed where vibrations are minimal is about 75mph/4kRPM. I can comfortably cruise at this speed for at least an hour before my legs start cramping, but that's an unrelated problem. Going up to 80mph/4800-5000 RPM the vibes get more noticeable. I can sustain this for about 10min before vibes numb my hand. From 80-85mph/5k-5300RPM, I can resist the vibes for about 2 minutes but they're pretty intense at this point. my right (throttle hand) in particular really feels the vibes, I'm starting to wonder if a better throttle could solve this problem.

Keep in mind that my carbs are set up pretty good, but I havn't confirmed that they are perfectly in sync. Synced carbs are essential for reduced vibrations, incase you didn't know.

Hopefully this will give you an idea of changes you could make to your gearing if you would like a higher comfortable cruise than me. I went with this gearing because I still wanted to have the off-the-line acceleration for city riding. this may not be an important factor for the riding you do...