Hi all. I'm in the midst of giving my 1994 900 Monster a rebuild and I've come to a bit of a hurdle. How in the world do you get he primary gear off the shaft. The nut came off easy enough so I whipped out the old trusty puller and tightened it up but there's nothing happening. Had the heat gun on it for about 10 mins this evening and tightened the puller some more but still no sign of movement. So, anyone know where I can hire a decent puller to do the job? I did notice when I was stripping the bike that 1994 must have been the year that allen head bolts were made mainly of cheese. The hex has just corroded away on quite a few, meaning I've had to drill 'em out, especially the one's on the front of the motor.
I have just split my engine and the primary gear was the one thing that defeated me. I just left it there after it laughed at my feeble attempts to get it off! But apparently you need a pretty epic puller to get it off, oh and put the nut back on a few threads or it shoots off like a rocket when it finally gives!
It took a special Ducati tool at JHP, a big bloke, and a heavy mallet to get mine off. They did it for free so no complaints, but it's a brutal job. Before spending any money i'd try a similar dealer/independant route if i were you. I'd actually bought a real heavy duty puller, and had a 2 foot breaker bar on it and yes, it broke. LOL.
The factory tool is like this; DUCATI 748/916 FACTORY SPECIAL PRIMARY TOOL PULLER | eBay but there are cheaper ones available. You may get it with a heavy duty puller but access around the gear is a problem. Where are you based? I have a puller like this and it only takes few minutes (still need heat & big hammer) to get the gear off with it but I don't want to be sending it all round the country. If you are local to me you could pop over and borrow it.
Thanks for the replies and thanks to Dukedesmo for the offer, thing is I'm up here near Newcastle so a bit far away. I'm going to call in at a couple of local garages tomorow to see if they can help. Doug
You'll defo need a good puller, but as an aside.....leave the nut on the end of the crank. When it does go, it goes big time and if there's nothing to stop the gear and puller comin off something/someone will bet broke or hurt.
Couple of questions if anyone could answer. I plan to strip and split my 900 engine. 1. If I don't pull the primary gear can I still spilt the engine and/or what are the problems. 2. If I do pull the the primary gear how do you get it back on. Cheers Gaz
Thanks Mr.R thought that might be the case. Suppose I should have looked at my manual as well rather than just asking questions. Just had a look and realised its on a tapered shaft so the installation procedure now makes a bit more sense, (thought I would have to push it down a long length of parallel shaft). I presume with the heads and barrels off I can lock the crank through the top piston pin hole in the connecting rod or would you use another method. I know this sounds a bit daft but I just want to take it to bits to basically say "I've taken and engine to bits" and put it back together and to improve my knowledge. It's only done 12k (quite sure it's genuine) and probably does not need to be refurbished - would you change the expensive main bearings while it was split with this mileage. I am not bad technically but would anyone strongly recommend against it if you did not have to split it. The only thing that concerns me is buying or hiring expensive tools. After taking the primary gear off are there any other problematic things like this to do. Thanks again, Cheers Gaz
Unless there is a need,I wouldnt strip the motor.If its running fine and dandy I would leave it be.If you want the experience,why not buy a knackered one.Take your time to strip,rebuild,clean,polish and generally refurb that one.Then you have a known good spare just incase.It would end up being an expensive job aswell.So spread the cost over time..
Not a job I would take on lightly, do you know how to pre load the bearings? I don't, one or two jobs better left to them that do. Steve
Thanks for replies all. Yes I had read the that if you replace the main bearings they must be preloaded, just looked at figure 0.15mm in haynes manual (will check Ducati manual). Simplifying it - measure a few bits, add some measurements together, take some measurements away from some other measurements and you have total shim thickness and divide by 2 to get shim thickness on each side. Regarding taking my time I am ridiculed in my family for taking my time. I have had the bike 2 years already so I am spreading the cost. I am lucky I might make IOM TT 2014:biggrin: The pre load does not worry me just need to make sure I can get the primary gear without too much expenrce. Appreciate your thought but still can't see anything that's too much of a drama. (note to self - I could end up eating these words) Come on peeps give me something else to worry about :biggrin: and I might leave it alone. Cheers Gaz
I'm all for "If it ain't broke, don't fix it". Mine's got 40,000 on it and I'm only doing it as I saw what looked like small metallic bits on the oil strainer last time I changed the oil and the fact that it seemed to take forever to build up enough oil pressure to extinguish the warning light after the oil and filter change. I always turn it over without the plugs in to get the oil circulating before firing it up after I've changed the oil and filter , but it took ages for the light to go out. So my first thought was low oil pressure caused by worn/knackered big end bearings. I've just checked the pump clearances today and all seems fine there. Tomorrow I'm calling in at a local independent bike workshop to see if they have the necessary puller, fingers crossed.
Sometimes best to check the easiest, cheapest components first, like the oil pressure sensor. If its gummed up, as it might well be after 40,000 miles, a quick clean might see your oil light change much more quickly. It won't however explain the metal debris in your oil strainer Good luck
It was the presence of metallic bits that convinced me to dive in, that and the fact it was burning a bit oil, the paint was also coming off the engine cases in sheets making it look like crap. The frame also had quite a few rust spots so I though I might as well do the whole lot. I've had the bike for 19 years and used it through many winters on our salt encrusted roads, it was, to be truthful, looking a bit sorry for itself.
Correction The statement about getting the shim thick ness and dividing by 2 is not altogether correct. This is only Ok if the crank case depth are the same -which they probably will not be. The calculations/explanation is in the Haynes manual for the Left and Right side shims, but all you do is get half the difference in the crank case depths and add/subtract from half the total shim thickness to position the the crankshaft centrally. Sorry. Some report 0.15mm is a bit much preload any thoughts anyone. Found a 10 ton puller at RS online (349-7227) for £66 hope gear is not smaller than 50mm. Cheers Gaz.
UPDATE !! Got the bugger. Local garage that does mainly cars has just started doing minor repairs to bikes as well as MOT's. Took it to him after work tonight and after 30 secs with a big two leg puller off she comes with a mighty crack. Didn't even charge me for the service. Yippeeee.
