MrBenn
Hi all,
I apologize for such a mediocre question (again). I'm armed with a Ducati manual and the internet and with just those tools I am trying to build a bike. I don't have friends with Ducatis either to phone them and ask. Any Japanese bike rider usually answers with "you bought a Ducati!" whenever I phone to question anything.
Armed with my limited knowledge and a huge bucket of enthusiasm I have stripped my S4 engine right down as a result of a "knock" that it had before the engine was torn out. Upon getting to the bottom end I am pretty sure somebody has been in there previously (I've had it too long to take it up with the previous owner now). All bolts seemed nicely copped greased and not overtight and the cases came apart without too much of a problem.
There is writing in white pen on the crank. I would normally presume this means it is a second hard part but I didn't know if anybody has ever torn down an engine to find letters and numbers written upon the crank.
If it has been taken apart before that will give me a little more information about what the problem is. I haven't actually removed the crank or cleaned it because I didn't know what this writing is for. There seems to be quite a lot of side to side movement on the rods but as this is my first play with a Ducati it is all learning experiences.
Thanks all
Mr.R
There's often writing/numbers on the crank and primary gears etc.
It's there so the factory builders can match parts together.
Matched parts are marked to keep them in balance, or within factory tolerances. 😏
Most of the cranks and primary gear sets that I've seen are marked in this way.
Steve R
MrBenn
Thank you
Thank you Steve R...
I think I will treat it as never being rebuilt then and replace all bearings etc while I'm in there. I'm not keen on doing this again in a hurry.
I'll remove the crank tomorrow and see if the bearings are as worn as I think they might be. If they are then it will all be worth it.
Cheers,
Alan
marvin
MrBenn wroteThank you Steve R...
I think I will treat it as never being rebuilt then and replace all bearings etc while I'm in there. I'm not keen on doing this again in a hurry.
I'll remove the crank tomorrow and see if the bearings are as worn as I think they might be. If they are then it will all be worth it.
Cheers,
Alan
Personally I might put in new rod beaqrings but if the mains looik and feel OK I would just put them back in. Ball type bearings don't give much trouble unless run low or without oil. I would rather have a fine old bearing than a new one. Ball/roller type bearings will usually go out soon after new if they're going to. If they don't they're probably good for a lot of miles.
Just my 2 cents!
MrBenn
marvin wrotePersonally I might put in new rod beaqrings but if the mains looik and feel OK I would just put them back in. Ball type bearings don't give much trouble unless run low or without oil. I would rather have a fine old bearing than a new one. Ball/roller type bearings will usually go out soon after new if they're going to. If they don't they're probably good for a lot of miles.
Just my 2 cents!
.
I appreciate the input - Thank you. I was just in the shed checking them main bearings and they seem solid and do not look particularly worn. I could feel no side or up and down movement on them at all. I will check the rod bearings tomorrow. So far all looks quite good in there. The only problem I can find is one that I did and I have been intending to address it anyway (I snapped part of the layshaft end where it holds onto the water pump. It works but will no doubt play on my mind and fot the price of a used shaft I may was well throw a replacement in while I am at it). I have to say that having grown up on 4 cylinder bikes the Ducati engine is better built than I thought it would be. Too much press hype on build quality perhaps.
I have been reading so much and watching many videos on the crank end float adjustment and heating cases/freezing bearings. I had almost put myself off doing them unnecessarily.
marvin
end play
Yes, set the preload on the crank. I was told by a well known engine buillder to set new bearings at .004" preload and .006" on used bearings. It is important that they have preload as they are linear thrust bearings. I should also have a used layshaft if you can't find one locally.
Brad Black has a good blurb on preload on his site. (bikeboy.org)
p.s. Or angular contact or whatever they're called ! And yes, they're pretty much bulit proof if you use 20-50 oil in them and don't over-rev them!
MrBenn
marvin wroteYes, set the preload on the crank. I was told by a well known engine buillder to set new bearings at .004" preload and .006" on used bearings. It is important that they have preload as they are linear thrust bearings. I should also have a used layshaft if you can't find one locally.
Brad Black has a good blurb on preload on his site. (bikeboy.org)
p.s. Or angular contact or whatever they're called ! And yes, they're pretty much bulit proof if you use 20-50 oil in them and don't over-rev them!
Brads site has so much information on it. Its a true encyclopedia of Ducati fiddling.
I have found a layshaft - its only £20 so ive ordered it tonight. I knew it needed doing so its not the end of the world. I have seen several different measurements for end-float and had seen the 0.006 on this site - it was where I was going to be heading for in all honesty.
Last time I built a bike up I promised I would never do it again and here I am doing exactly the same thing all over again. 😁
griff851
Read up on using 'platstiguage. In the shop we had a set of shells used to measure up, then would fit the new appropriate shells (yep they come in different thicknesses). Remember to fit the rod spacer gauge to take up the end float, otherwise wise the plasti gauge becomes difficult to read as the rod cocking off squishes it on one side. Might pay to stick a dial gauge and check the up and down movement before you pull it apart. I think it's 0.025- 0.060mm clearance for the journal to plain bearing.
Avoid using 0.2 crank shims if you can when setting crank preload, they have a tendency break up. You must have some preload to stop the ball bearings skidding.
marvin
Actually, now that I think about it,,,,probably .006" for new bearings and .004" for used bearings as the new bearings would "wear in" just a bit.
Griff, I just had a 999S crank balanced in Asheville by an older gentleman who builds engines for NASCAR. He won't use plastigauge because he says it isn't accurate enough. He measures/calculates everything. FWIW
MrBenn
griff851 wroteRead up on using 'platstiguage. In the shop we had a set of shells used to measure up, then would fit the new appropriate shells (yep they come in different thicknesses). Remember to fit the rod spacer gauge to take up the end float, otherwise wise the plasti gauge becomes difficult to read as the rod cocking off squishes it on one side. Might pay to stick a dial gauge and check the up and down movement before you pull it apart. I think it's 0.025- 0.060mm clearance for the journal to plain bearing.
Avoid using 0.2 crank shims if you can when setting crank preload, they have a tendency break up. You must have some preload to stop the ball bearings skidding.
Thanks Griff. Im quite the fan of plastiguage. Its helped me with many tasks over the years. Great idea, I will order some now - I doubt the stuff I have lurking in the shed will still be pliable. The last engine I built up was a GSXR k7 engine and that had different colour references for different shells. Was a bit confusing until I actually had them in my hand then suddenly it made sense. I haven't dedicated too much time to looking for bearings but I have seen talk that they are not the easiest thing to find but hopefully all will be okay. I need to break them out to see whats going on with them.
The dial gauge is currently en-route from a seller on eBay. As said - it all seems very well put together. If the crank is damaged it wont be the end of the world - I am toying with a 900 crank anyway but I wont buy one unnecessarily as I cannot imagine that the additional few cc's will really make that much of a difference.
marvin
Your rods should have either an "A" or a "B" on them. Bearing shells are also colored, either red or blue to fit either the A or B rods. I have that info. someplace if you want it. I got some "red" bearings from
www.ducatiomaha.com Probably a stretch for you guys across the pond!!
brad black
ime you'll need 2 of the blue shells in each rod to get the clearance down to the least you can, otherwise it'll be at the high end if you go the manual way.
replace the rod bolts.
MrBenn
Thanks again
Well, I'll be out in the shed this afternoon and lift these rods off.
Looking for the rods I think I have found some over here. I just need to check availability.
It seems weird they are sold singly though as it would seem like a bad idea to just change one half of the bearing.
Regarding the bolts, Brad - will do, definitely. Again its inexpensive insurance against catastrophic loss.
Again, really appreciate the guidance on here chaps, its really appreciated.
MrBenn
Well, well, well..
So, I split the cases, removed the rods and the bearings seem OK (but worn) so my initial concern over no and up and down movement seems okay. I checked all the gearbox over looking for something nasty - again that appears okay.
When testing the bearings I think i have found the reason for the noise. On one side the main bearing spins nice and freely, on the other it drags and crunches as it turns. I cannot see anything wrong with the bearing physically but it certainly drags and grinds when spinning it. Its the crank bearing on the water pump side of the engine. This displeases me and makes my job seem less fun as it appears those bearings are not the most fun thing to fit in the world. The only time I have ever encountered a problem with such a bearing the race was loose and it was falling apart. This seems okay - just "notchy" on turning.
So, Im now wondering "should I just buy a replacement motor".. I guess Im safe in thet I know the gearbox/crank/rods/pistons and heads are OK. The barrels do look a little worn but no major scoring. Its probably best just to build it up I think.
At this moment in time the engine is destined for an S4 frame but looking at 888 (replicas) based on monster frames I think Im best to get an 888 or 851 frame at some point in the future. The legal side of chopping a race frame about and using the S4 headstock/front section doesn't appeal tbh. As this means Im not in a hurry I guess I should build it properly and do it right!
Just thinking out-loud here!
Thanks all.
griff851
Piece of cake, stick them in the oven (pull studs if you have a small oven, and try not to get caught by missus, clean cases well to help avoid detection 😁) at 180-200°C, drop the case on to wood on the bench and they fall out. The new bearing need to be chilled in the freezer. They should fall into the hot case's, but have a drift the same as the outer bearings diameter on hand. If they cock early, abort and tap it out. Re- chill and heat cases and go again. If they cock late you can usually recover the fit, but don't piss about. If in doubt abort and repeat rather than swear and bash. Note also it's angular contact so it goes in only one way. PITA when you have to turn it around. Heat transfer expansion of the bearing is pretty quick.
marvin
LOL! Or, you could go to the used appliance store and buy your own oven. That way your next pie won't taste like Motul or Rock Oil !!
MrBenn
griff851 wrotePiece of cake, stick them in the oven (pull studs if you have a small oven, and try not to get caught by missus, clean cases well to help avoid detection 😁) at 180-200°C, drop the case on to wood on the bench and they fall out. The new bearing need to be chilled in the freezer. They should fall into the hot case's, but have a drift the same as the outer bearings diameter on hand. If they cock early, abort and tap it out. Re- chill and heat cases and go again. If they cock late you can usually recover the fit, but don't piss about. If in doubt abort and repeat rather than swear and bash. Note also it's angular contact so it goes in only one way. PITA when you have to turn it around. Heat transfer expansion of the bearing is pretty quick.
You make it sound like some sort of dangerous adventure. Im looking forward to it now!
Marvin - I wonder if they would let me use their ovens to "test" the quality of the products they sell?
That way it costs me nothing, my wife doesn't kill me and my food continues to taste good without the faint aroma of oil and bike-fluids.
MrBenn
Bearings - Straight to Ducati?
It looks like the internet has 1/10th of it dedicated to saving money on Ducati bearings - so much so I am confused.
It looks to me like I can try and save a few quid and buy bearings from any number of places but nobody seems 100% sure if they are as good as OEM. Doesn't this mean I should just buy OEM bearings from Mr Ducati and enjoy paying the Ducati-Brand-Tax?
Ive found bearings in the US, Germany, South Africa but not the UK.
Usually I would just contact the local dealers but I cannot find any Ducati OEM sites that sell things in the UK if I don't want to buy an entire bike (well, obviously I want to buy an entire bike but wheres to fun in that). Have I just over done the internet and burned out?
** My local Ducati dealership is 50km's from here - I'll give them a bell tomorrow - Looks likes consensus is to buy genuine bearings **
griff851
You could try negotiation. Either passive or aggressive, depends on your relationship. “Honey the oven looks a bit dirty I’ll clean it for you because you are my world”. Or, “woman you filthy cow, no wonder dinner is always crap, i’ll Clean the oven again...” But first I just have too..”
Alternatively go to bed, wake up a some stupid hour, do the cases like elves making shoes, clean the oven and time it so the wife wakes up and finds you cleaning, and score full points. Don’t forget to blame the neighbors for the kitchen smelling suspiciously like an oil refinery. Have flowers ready as a back up, just in case you hear something about stupid bastard or divorce. 😁
Ps maximum expansion is at 220°C
MrBenn
griff851 wroteYou could try negotiation. Either passive or aggressive, depends on your relationship. 'Honey the oven looks a bit dirty I'll clean it for you because you are my world. Or, 'woman you filthy cow, no wonder dinner is always crap, i'll Clean the oven again... But first I just have too..
Alternatively go to bed, wake up a some stupid hour, do the cases like elves making shoes, clean the oven and time it so the wife wakes up and finds you cleaning, and score full points. Don't forget to blame the neighbors for the kitchen smelling suspiciously like an oil refinery. Have flowers ready as a back up, just in case you hear something about stupid bastard or divorce. 😁
Ps maximum expansion is at 220°C
You speak like a man with great experience in such matters. Hat doffed in your direction good sir! Muttering the word "filthy cow" will probably shorten my lifespan though. I might avoid that but pretty much everything else makes sense. 😄
At 220°C will the existing bearing come out without much trouble or will I have to be armed with gauntlets, masks, blacksmith hammers, sockets and swearing?
On another topic altogether thanks for your comment - its cheered me up no end 😄
