YPVS Engine Split

[ps350ypvs]

Hi All,

I have just removed the engine from my 31K YPVS 350. I would like to take the top engine case off to get at the crank. Having not done this in a long time and not having brought the manual to work with me a bit of advice would be gratefully received.

I have removed all the bolts which bolt in 'downwards' what else do I need to remove to split the engine case? Also how do you 'thread' the wire form the charging system through the top case?

Any help will be most gratefully accepted

best regards

Paul

[LC_BOTT]

I haven't done it that way myself before, remove stator + flywheel as mentioned, carefully pull out the rubber grommet and the cable and plugs will fit through the hole, don't forget you will still have to remove the top casing bolts, as these also connect top/bottom cases together.
It might be worth checking an online manual if in doubt.

[dusty350]

Hi
Clutch basket has to come off to get to the bearing retainer plate that is situated behind the basket. It bolts between the upper and lower cases. Best to undo as much as you can before you try splitting the cases as certain nuts can be very difficult to remove. Are you doing a crank rebuild ?

Dusty

[fredrikspansk]

I use the Haynes manual and this on youtube 



/Fredrik

[ps350ypvs]

Thanks to you all. Had to pull the flywheel with a 3 leg bearing puller it popped off like champagne cork! Got the stator off and have only the big nut on the clutch basket to go

thanks and have a great christmas

Paul

[dusty350]

Hopefully your rotor is ok - they don't like those "legged" pullers as they can damage the rotor edge, so check it over.
That's a useful video, and life is easy if you have the pneumatic rattle gun. Not all of us have though, so make sure you use the right clutch holding tool to remove the centre nut on the clutch. They can be really tight, and may be a 2 man job if you are doing it with a normal wrench. Interesting as well the guy in the vid says don't bother with the bearing retainer plate behind the clutch. Yamaha put it there for a reason - to arrest excessive sideways play on that bearing when the clutch is actuated. Maybe you can get away with no refitting it but why wouldn't you ?? It's only 2 screws to fit it back on, and they are still available new as some do break, or are missing. "Belt and braces" maybe, but no reason not to re fit it imo.

Dusty

[ps350ypvs]

Dusty the flywheel has got to replaced due to rust and i will be fitting a new stator as well. Do have access to a impact gun and the right size socket and will not be missing parts on re-assembly.

Many Many thanks for your help as the top case is off for bead blasting in the morning

thanks again

Paul

[dusty350]

Enjoy the rebuild.

Dusty

[Yogi]

Dec 19, 2017 16:54:56 GMT 1 fredrikspansk said:

I use the Haynes manual and this on youtube 



/Fredrik

I wouldn't let that butcher nowhere near one of my engines

[davey]

Have to agree with Yogi , ive watched a few of this guys vids and butcher is a very apt description .
There is lots of info he puts out that to the novice could get them into sh-t , not that im a pro but i ask on here if i need help not from some untrusted u tube video.
This forum to the new ones coming on board is imho the best source of good and accurate info . Keep up the good work guys , you know who u are and without you guys and this forum both my bikes would still be unused in the garage

[JonW]

Eeek... butcher indeed.

Get a manual OP, cheap insurance...

[dusty350]

Yea I agree too. He had that apart in the time it takes me to gather my tools ! I think it's useful from the point that it shows that these engines are easy to strip. It's the way he does that it is not great. The fact he has the rattle gun doesn't really help the guys that don't have one. Getting the nuts off the end of the crank and the clutch is often the more difficult part of the strip down as they can be so tight. Be interesting to see where he lobs all the parts he removes, but it doesn't look like they get much care. And as said, why say not to refit the bearing retainer ?? What were Yamaha thinking, putting that "useless" part in the engine for all those years !!. There are far more useful threads on this forum for sure.

Dusty

[rd350rob]

Was just waiting for him to bring out the brick and crowbar!!
I like the noise where he's removed the clutch springs- sounds like he's lobbed them over his shoulder!!

[abar121]

To those that don't have a rattle gun, get one! Crank nuts, sprockets, clutches etc etc. A couple of taps and they are off.

It's saved me a load of hassle, skinned knuckles and trashed bolts.

[ps350ypvs]

Just a quick question before I start on the clutch basket with large impact and BIG socket, are they left handed thread?

Thanks as always (this would not be any where nearing its current state without you people)

Paul

[markhoopy]

Dec 20, 2017 11:34:02 GMT 1 ps350ypvs said:

Just a quick question before I start on the clutch basket with large impact and BIG socket, are they left handed thread?

No they are a right-hand thread.

[ps350ypvs]

Thank you job done frame off to powder coaters and long list of new parts on order!! I am looking froward to getting nice new bits and fresh coated bits after all the nasty grime and old bits off

Paul

[fredrikspansk]

Yes sorry for that bad link i was to quick there to link it
It`s terrible.

I used that only to get a quick look at a strip down
that is not how i do it .



/Fredrik

[ps350ypvs]

Fredrik the video was still of some use as it showed all the parts that needed to come off first. It along with all the great help you all gave meant the job went smoothly with no damage. Today the Haynes came into work as well but the help and advice offered here is so useful and the wealth of knowledge means avoiding any damage or mishaps

again really grateful to you all especially Dusty I will start to post pics of the rebuild in the new year as parts arrive from refinishing and as always will be seeking advice. I find that I like being re-assured that the method I am about to use is correct or is there a little trick/knack to doing a certain job. The 1/2" impact gun really helped with the clutch basket nut and drive gear nut

Paul

[ps350ypvs]

Any recommendations on getting the crank refurbished and are their 'uprated' bearings available for the gearbox shafts?

Paul

[dusty350]

Hi Paul
I always use PJME in Wolverhampton for crank rebuilds and rebores. Been going there for years and always been really happy with the service and quality of the workmanship. The owner - Paul Vetere is a member on here. I know a lot of guys use Grampians and they come highly recommended too. Norbo does an exchange service on recon cranks as well, so worth bearing in mind.
Regards gearbox bearings - I've always used genuine Yamaha bearings. Whenever I do an engine build I always replace them for new, but to be fair I've never found a worn or knackered bearing when I've stripped them out, so on anything other than a mega horsepower, big bore engine I would happily go with standard Yam as I know they last. Or an alternative bearing from a quality manufacturer, but one of them especially is hard to find elsewhere.
Enjoy the rebuild - you get a lot of satisfaction from doing it yourself

Dusty

[markhoopy]

Dec 20, 2017 15:18:07 GMT 1 dusty350 said:

Hi Paul
I always use PJME in Wolverhampton for crank rebuilds and rebores. Been going there for years and always been really happy with the service and quality of the workmanship. The owner - Paul Vetere is a member on here. I know a lot of guys use Grampians and they come highly recommended too. Norbo does an exchange service on recon cranks as well, so worth bearing in mind.
Regards gearbox bearings - I've always used genuine Yamaha bearings. Whenever I do an engine build I always replace them for new, but to be fair I've never found a worn or knackered bearing when I've stripped them out, so on anything other than a mega horsepower, big bore engine I would happily go with standard Yam as I know they last. Or an alternative bearing from a quality manufacturer, but one of them especially is hard to find elsewhere.

Dusty

+1 on all of this

[ps350ypvs]

Thanks guys. I agree that the bearings l;ook in great condition but whilst apart it seems the only way is to change all bearings and seals while you have the chance. I have spoken with Norbo about the crank but am about to ring PJME so once again big big thanks. The barrels are with Stan Stephens at the moment for rebore new pistons and basic tune. The engine top has gone to get bead blasted and the engine sides are off for a blast and powder coat. I love when getting to this stage as once the frame. is back from powder coating it is actually time to start rebuilding. Stripping down to frame means tha every part is cleaned replaced or refinished so that when all is done iot should look and ride wonderfully. I will post pics of the build as it comes along

And I know you already know but this would not be happening without all your help and advice

Regards

Paul

[Tobyjugs]

I skipped through the video very quickly. We all have different opinions over what is good and bad so just out of interest state the worst thing the man did in the video?

[jon]

As stated before, possible the worst bit was advising not to fit the retainer. This bearing is a dual row ball bearing for a reason, as it takes linear as well as axial play like most bearings. This helps keep the bearing located in the linear axis as the clutch push rod puts stress on it.

I also didn’t like the way he refers to the Philips screws. They are JIS screws and will of course be rounded by a Phillips screwdriver. This lack of knowledge makes you wonder what else he is unaware of.

Apart from that it’s just his general throwing the engine and parts around.

Jon

[Tobyjugs]

Any one else or has Jon summed it all up?

[lrcarl]

Don’t like the way he tried to chisel out the
Crank half ring.straight in with hammer and
Screwdriver
Carl

[jon]

Dec 20, 2017 21:26:50 GMT 1 Tobyjugs said:

Any one else or has Jon summed it all up?

Oh, and I forgot to mention he suggests any slack between the clust basket and secondary drive means the rubbers have gone.

Small play is normal OEM, only excessive play means the rubbers are gone.

Jon

[budgie]

The guy is a freaking animal....glad he’s not rebuilt any of mine..!.. hardly clinical conditions....🤔

[abar121]

Looking at his vid putting it back together, that is a monster amount of sealant on one side, then he puts the same on the other!

There will be loads floating around inside the cases, just waiting to block something up.