Engine rebuild

[quant55]

My engine (VR90) need to be rebuild. After inspecting the plane bearings I decided to replace them. The crankshaft looks fine, but the plane breaings are gone. So I started to snipe for the journal size markings on the crankcase, crankshaft, connecting rods and counter balancer. I found the stamped marks on the crankshaft, I found also the marks on the crankcase. But the ink marks on the counter balancer and those from the connecting rods are gone or unreadable.

 

Can somebody offer an alternate method to determine the "color" of the plane bearings… something based on the measurements of the old bearings maybe. I'm somehow disperate as I don;t know how to handle this. Please help.

 

Regards,

Corneliu Tanasa

[bongobobny]

You could use as product called plastic gauge or plastigauge to determine the correct size...

[quant55]

do you have more details please?

[bongobobny]

Here's a link...

 

http://www.plastigaugeusa.com/

 

It's use is primarily for engine rebuilds but has other uses as well.

[dingy]

There are numbers engraved on the lower crankcase, 2 digits over 4 digits on one side and 2 on other. Left side lower 4 digits are crank main bearing size, upper 2 digits are balencer shaft sizes. Don't know what right side numbers are for. On the crank, there is a 4 digit number stamped on it and a 2 digit number, and a 2 digit number on the balancer shaft. Each rod will have a number on it, usually ink stamped on, not stamped or engraved, I think each starts with an 'E', but not always. Letter doesn't matter, only number.

 

The case & rod numbers are 8 to 5 range, the balance & crank shaft are 0 to 4 range. subtract the shaft numbers from the case numbers to get the bearing sizes.

 

See attached PDF cut from service manual, and a picture of bearing markings on case.

 

Most bearings are in mid range, #'s 4 & 5. That is design tolerance factory tried to hit.

 

Plastigage is a real chore on the block, Block halves need to be reassembled with sealer, then split to read plastigage. You need a known size bearing in place, so you know which way to go if reading is incorrect. Then do it again. Rod bearings, are much easier to plastigage.

 

Almost all motors I have torn down have had color markings unreadable on bearing s. There is a thin strip on edge, in middle of arc on one side of bearing.

 

The videos that are available for $20 for VMax motor, go into bearing selection in depth.

 

Gary

 

82448.pdf

 

[ATTACH=CONFIG]105715[/ATTACH] [ATTACH=CONFIG]105716[/ATTACH]

Edited June 5, 2016 by Freebird
Corrected bad info on number positions

[quant55]

Thanks Gary. I hope to manage to get the info I need based on your help. If not I'll come back with pictures from the crankcase, shafts and rods.

[dingy]

Picture attached of numbers on balancer shaft & rod.

 

E7 is number that is important.

 

Easier to send pictures here than to reply to your PM, can't attach pictures in PM.

 

Gary

 

Edited June 5, 2016 by Freebird

[quant55]

Ok Gary, thanks. Today based on your pictures, I found the marks on the counter balancer. About the conecting rods, here are 3 pictures. It looks to read 9A7 but… and I'll wait for your opinion, is this the expected mark? Which is the digit to be considered?

 

PS I have also the marks from the crankcase but I'll post them in a separate reply.

[quant55]

Gary, now about the crankcase. Here there are the two images. Please help me understand the meaning of them. Also I attached the crankshaft and counterbalancer. Thank you.

[dingy]

Bearing sizing has been corrected in this post, see thread 13 for clarification. Gary

 

I gave you wrong info in 5th post above, I looked at engine video & am correcting it here & I will edit that post.

 

Error was in case numbers engraved in block. Only the numbers on left side are needed for bearings, upper 2 numbers are balancer shaft, lower 4 numbers are crank mains. I don't know what right to numbers are for.

 

Numbers shown below are what they appear to read to me looking at picture.

 

1st line in 1st & 2nd group are case numbers. 2nd line is numbers on crank & balance shaft

 

3rd line is subtracting 2nd line from 1st line and it is number of bearing needed for that journal.

 

3rd group is showing 7's on rods, I am guessing 4th rod is a 7 as all rods I have seen are 7's and rods shown in video are all 7's. Rods are easier to machine than crank or shafts so they will tend to be more consistent. rods. Both journals on crank appear to be '3', there are 4 rods so you need 4 sets of bearings. Therefore all 3's in the crank rod row. Subtract 2nd line from 1st line and it is number of bearing needed

 

All bearing sizes are read facing front of motor, left to right.

 

Case/Mains 6 5 5 6

Crank/Mains - 2 3 3 3

Main Bearings 4 2 2 3 Left out

Brown (size #3) on Outer Left main (J1) - Black (size #2) on Inner Left main (J2) - Black (size #2) on Inner Right main(J3) - Green (size #4) on Outer Right main (J4)

 

Case/Balancer 7 6

balancer - 2 2

Balancer Bearings 5 4

Green (size #4) on Left balance (J5) - Yellow (size #5) on right balance(J6)

 

Rods 7 7 7 7

Crank Rods - 3 3 3 3

Rod bearings 4 4 4 4

 

Numbers don't line up right when I post this so you will have to mentally line them up. I attached a screen capture of numbers formatted better.

 

Gary

Edited March 15, 2014 by dingy
Added 7's to rod sizes

[quant55]

Thank you Gary. Based on the info you provided these were my results also. I think that I properly understand and now I am ready to order my spares

[quant55]

Gary, my bearings came from the manufacturer, so I started to look at the engine to replace the old ones with the new ones. Looking at the old bearings I found some traces from the old colors.

 

The good news is that the old color matches the bearings ordered. The bad news is that I found in the engine the brown color (3) in the J4 position and the green (4) in the J1. From my understanding from the service manual is that the J1 is near the flywheel… is that correct?

 

Also, the counter balancer the new and old color matches, but they looks to be reversed. From my understanding, the balancer bearings should be yellow (5) and green (4). Which one should be on the right of the engine and which one on the left? (see the pictures from my previous posts please about the marks: 7 6 on the case and 2 2 on the balancer). Is the (5) on the right of the engine and the (4) on the left?

 

Thank you,

[dingy]

This is bad news and good news, once again I messed this up. I'm blaming old age and a weird way of numbering from Yamaha.

 

The Bad news.

 

The crankcase #'s are read in the order they are inscribed on block. However the markings on crank & balance are read opposite. Journal # 4 is first number on crankcase, far right journal viewed as though you were sitting on bike, but on the crankshaft it is the last number. Same with balancer shaft.

 

The good news.

 

Due to the way your numbers are numerically & order. You have the correct set of bearings ordered.

 

All bearing sizes are read facing front of motor, left to right.

 

Case/Mains 6 5 5 6

Crank/Mains - 2 3 3 3

Main Bearings 4 2 2 3

Brown (size #3) on Outer Left main (J1) - Black (size #2) on Inner Left main (J2) - Black (size #2) on Inner Right main(J3) - Green (size #4) on Outer Right main (J4)

 

Case/Balancer 7 6

balancer - 2 2

Balancer Bearings 5 4

Green (size #4) on Left balance (J5) - Yellow (size #5) on right balance(J6)

 

 

Rods are all the same.

Rods 7 7 7 7

Crank Rods - 3 3 3 3

Rod bearings 4 4 4 4

 

Call me if this does not seem right, I have done this several times and typing it out is confusing as heck. Number is in profile.

 

A second look at it by Skydoc_17 or Squidley, 2 I can think of, would be great. I am going to send them both a PM to look at this.

 

The videos make this much clearer, they are worth the money.

 

Gary

 

 

Edited March 15, 2014 by dingy

[skydoc_17]

Dingy's post #13 is correct. I label the engine block before I remove it from the frame, and this helps me to keep oriented when the block is on the engine stand. The Videos that Dingy are talking about are worth their weight in gold because if you get disoriented during the tear down, or reassembly, you can pop in the DVD and SEE IT instead of reading it. Much better visualization, in my opinion. Remember, patience will net you a running engine!

Good luck with this project!

Earl

[quant55]

Gary, I'll double check tomorrow the way the main bearings were installed, but myself I figured out exactly the same positions as you mentioned for both main and balancer bearings.

The odd thing is that old the J1 and J4 bearings were installed reversed… and also the balancer bearings were reversed also.

 

As I'm not the first owner of this bike, I assume someone worked inside the engine and messed up with the bearings. The fact is that J1 and J4 were almost destroyed. See the attached pictures of the down half of the bearings. The inversion of J1 with J4 I think it might explain somehow the destruction of the main bearings. I'll double check also the wear of the balancer bearings.

 

Another thing is that the crankcase has been hit by the crankshaft. See the fourth picture. And now I have at that point about 0.2mm clearance between the crankshaft and crankcase. Do you think this should be addressed also or I can live with this without any trouble?

 

I'll try to call you tomorrow after I'll double check how the bearings were previously installed for a final clarification. Thank you.

 

Edited June 7, 2016 by Freebird

[dingy]

Picture #4 looks bad, real bad. Those are machined surfaces at that point that control the side thrust of the crank.

 

I would not use that case, upper or lower as they are matched halves. But then I run the livin crap out of them.

 

Again, ask Skydoc_17 or Squidly for a 2nd opinion.

 

Gary

[Squidley]

I absolutely agree with Gary, 4th pic is toast. I personally wouldn't use that case assembly, and without and excellent welder and machinist you could be looking to have to replace it.

[dingy]

Attached is a picture of the exact same area as in your 4th picture. There is some light marking on the case in the area that yours is damaged. This is caused by side thrust of the crank touching this machined surface.

 

This is the 1300 block that is in my 83 (Tweety) now. Bike has had some extensive modifications to the power train and has held together at over 10K RPM's on a few occasions, so I am fairly sure this light marking shown in my picture is not fatal. Something else in your motor has failed to allow this contact with the rod.

 

The crankshaft has a machined surface near this area that has contacted it.

 

Gary

 

Edited June 7, 2016 by Freebird

[quant55]

As I previously told you, I suppose that this has been caused by that J1 J4 bearings swapping, that later caused the crankshaft to stay only the J2&J3 and probably causing it to balance from left to right and to hit that surface. I'm not seeing any other reason at this point and nothing else looks wrong. The side machined surface of the crankshaft looks good, without any sign.

[quant55]

I absolutely agree with Gary, 4th pic is toast. I personally wouldn't use that case assembly, and without and excellent welder and machinist you could be looking to have to replace it.

 

Thank you. I'm looking now on the eBay and it looks there is no good engine (or case) available for VR 86-93. I'll have to wait until one will become available. I'm thinking to run for a while with this case and I wonder what would be the impact? How soon should I expect other issues? The clearance is about 0.20mm.

 

Another question is if the case from RSV can be used with the cylinder heads from the VR90. (I have here nearby one available RSV for sale)

[dingy]

I don't think an RSV case will work. It's a small detail but an issue. The shift shaft that goes from clutch side to the left side is a larger diameter than the 1st gen shaft. They are not interchangeable without machine work to shaft.

 

A cosmetic issue I know of is the cylinder side covers are quite different on an RSV.

 

Another option would be 1983-1985 Venture, these a 1200cc motors so you would need the pistons & rods, crank is the same.

 

You could also put a 1200 VMax motor in it, 85-07. block is interchangeable, but you would need pistons, rod & crank. I am fairly sure Venture rotor will fit on VMax crank. I know someone to ask that will know for sure if you get a lead on a VMax.

 

Gary

[quant55]

Gary, I finally decided to go with crankcase replacement. In the same time, I'm just wondering what if I'll rebore the cylinders… but I'm seeing the PN for pistons are marked as obsolete. Looking at the later models I see the rods are the same, the piston pin and bolts are the same and even the piston rings are the same, but the pistons have different part number now. Do you have any idea if the 4XY-11635-00-00 (from RSV) can be used to replace 1NL-11635-00-00. What are the differences between the two? Thank you.

Edited March 31, 2014 by quant55

[dingy]

I am not sure if they could be swapped. The rings, wrist pin, circlip & rod's are all same P/N's.

 

The possible issue I see is that the crank is different P/N#, Where this might be an issue is the counterweight throws on the crank "MAY" have been made larger, and the piston skirts reduced in size to clear the counterweights when the piston is at the bottom of the stroke.

 

Other than that, they will fit.

 

Another thing that I just thought of is the top of the piston to the C/L of the wrist pin could be different. If it is shorter, compression would be low. If it is higher, valves will crash into piston.

 

Gary

[quant55]

I don't think so, because the engine is still 1300cc and the rings are the same so the crank should be similar. Also the crank bearings are the same...

[dingy]

I don't think so, because the engine is still 1300cc and the rings are the same so the crank should be similar. Also the crank bearings are the same...

 

I am not saying the ends of the crank that the rods are attached to are different, it could be that the central part of the crank has been made larger. The possible reason to do this is to increase low end torque of motor. I think this might be a low probability, because I know Yamaha reduced the mass of the rotor (flywheel). I don't see a valid reason to reduce mass at one point of the assembly, then increase it at another. I have an RSV rotor here which I am putting on the Hybrid/RSV/VMax/1st gen project. I know the rotor will fit on the crank of a 1st gen 1300 motor properly. This is tells me that part of the crank machining did not change. (Picture of motor attached for no particular reason).

 

The reason Yamaha would want the crank to have a higher mass on the crank assembly is that higher mass increase low end torque. Lower mass helps the ability of the motor to increase RPM's faster, it's one or the other. The RSV was a heavy touring bike, it needed the low end torque to get it moving smoothly, not the fast ramp up in RPM's.

 

This is just a worst case scenario. You asked if they would fit, I'm not going to say "He!! yes". My day job is a mechanical design engineer, so I am very use to looking at what can go wrong and not standing back and saying "Ship it"

 

Gary

 

Edited June 7, 2016 by Freebird