Friedom wrote: If only there was a tool designed for this very purpose. Lol
I did check the local parts store. Didn't have pullers with wide enough arms.
I'm actually very likely shipping off the whole engine so it can be worked on as a whole, matched, etc. But I might split the cases anyway just to say I did.
Tioli - you are talking about the difference in thicknesses here, right? They certainly look different in the picture, but pictures can be deceiving . . .
I will have to double-check, but I don't think the 220 is that far off between the two sides.
Yes that's it. That barrel is a 200 bored out to 220 so the difference is smaller but both my 200 barrels were the same. Offset by 2mm yet the head studs are centered to the boar.
That difference will have an effect on the port trajectory which is not nesseraly a bad thing. However it may help deside where the best place to put the rod is. Or it may be perfectly centred and that offset may be done on purpose to stack the charge a little.
I never worried about it as the motor was working just fine but now I find out you have to chose where to put your rod and if that's the case one spot is obviously better than the other.
If you have had that many motors apart you may have a selection of old pistons and rods. Have a look at the side ware on rods thrust washers and inside of the pistons for any sign of bias for ware. If there is a similar patten then there is the answer.
I am comparing left to right side not front to back.
When I measure in the middle of the main/front transfer port at a angle out from the centre it's about 2mm difference in thickness of the inner wall between boar and transfer passage.
Sorry for not posting photos it's just not that easy hear so I added two at the same place.
Tioli wrote:I am comparing left to right side not front to back.
So am I. One photo with the measurement is the left side of the cylinder and the other photo is the right side of the cylinder. Those are not the same side of the cylinder.
As I mentioned with the original photo, the lighting and shadows make the two sides look different.
Ok so it seems the 220 are even and both my 200 are offset as far as the thickness of the inner wall is.
I guess I will have to figure out what that means for me, it's only three choices left, right or centre. Then as you say it probably doesn't matter anyway.
I'm having trouble getting decent pictures. With no flash you can't see the readout and with the flash you can't see the readout. If you look really close on these, you can just make out the numbers.
Tioli wrote:Ok so it seems the 220 are even and both my 200 are offset as far as the thickness of the inner wall is.
I guess I will have to figure out what that means for me, it's only three choices left, right or centre. Then as you say it probably doesn't matter anyway.
I wish this came up a couple of weeks ago as I had a 200 cylinder on the workbench. I'll dig through some photos to see if I have one that might help.
I can't seem to find it, but I think you said the bore of the 200 is centered in the studs?
Yes from the top the studs are centered to the boar. Which you would have to do for the head. I think I remember the distance from boar to outside being different also.
Both my 200 barrels are 1997 so it could have changed over time. Plus the 220 barrel are a different casting so if it's a mistake it could be corrected then.
Then It may not be a mistake? Slightly different angled ports can be good for high rpm if you know what you are doing. Not me though I just know enough to not worry about it if every else is fine.
Hear is a wild idear that should never have been said. 200's have the crank set to one side, 220's centre and SR's to the other. I'm only saying SR's because the 220 head I got from Japan was a design RB had never seen before.
I don’t know how they bore the stud holes but one way would be to centralise on the boar and that way the head will be centred to the boar.
By the side it seems to me that there is a mismatch with the position of the barrel on the cases. I have not had my cases apart yet so can’t really see what I’m after but both times I had the barrel off the base gasket had to be trimmed so they didn’t protrude into the crank area. This could have been because I used two different brands of aftermarket base gaskets or the barrel is not lined up with the inside of the cases which I think is the case.
When I rebuild it I will check it thoroughly trim/fill where necessary and use OEM base gaskets
If you have a 220 apart put the locators pins in one half of the cases and sit the barrel on it. The inside of the transfer port from crank to barrel should be seamless without steps either way.
I measured a set of cases from a 200. The opening for the crank and location of the studs were identical between the two halves. If the 200 bore and studs are all centered, then when you put the cylinder on the cases, the bore is centered over the opening of the cases.
Centering the crank only makes sense then. When the crank is offset (which seems to be most of the time), I guess there is enough play in the conrod to compensate.
Yes I agree. Having said that I usually trim a gasket to crankcase first then sit it on the barrel and trim it that way if needed and both times it was so there is a mismatch I can’t investigate thoroughly till the cases are apart.
So I’m going in knowing the boar is offset, problem with barrel to cases and you have thrown in position of crank. Well, nice one.
Well my engine is off to millennium technologies for clean, plate, port, polish, split, crank, seals, bearings, tolerances, matching and reassembly. This time of year is for family, not being buried in the garage.
Now for the rest of the bike, it's a frame on wheels with front brakes. I pushed it around and coasted on it the other day to check the suspension. Looks like seals and rebuild are in order.
Going to get the frame sand blasted, then I think I'll do an appliance paint on it. Was going to powder coat, but doesn't seem worth the cost.
I need to press out the steering bearings before sandblasting, right? Any other bearings/things to keep in mind?