| Author | Message | ||
     Kyrocket |
Been reading alot about this gear lately, how the new bronze one is much better than the stocker. I have the bike semi-broken down right now doing some preventative maintenance. I have read here that the gearcase cover needs/has to come off but in the service manual it says you can just drop the oil pump. Can anyone who has experience with this shed some light on the subject before I take off more than I have to? Much appreciated. | ||
| Reepicheep |
Just drop the oil pump and you can look up there with a flashlight and get a 100% inspection. Rotate the engine a few times and recheck to make sure you see both sides, one side can look good and the other be toast. If you do want to replace it, you have to pull the rocker boxes and pull it out the cam cavity. So that gets more involved. So inspection is a simple matter of dropping the oil pump, 20 minutes and $1.25 for a new oil pump gasket. Replacement gets more complicated, but nowhere near what you are looking at if that pump lets go. I checked mine on the 9sx after 20k miles. It was worn, but still mostly there. I'll check it again at 30k miles and see how it is progressing. I have pictures in the knowledge vault for comparison... | ||
| Kyrocket |
Thanks Reep, can the gear be replaced just by dropping the pump or just inspected? According to the service manual it shows the gear coming down with the pump. | ||
| Reepicheep |
Thats the wrong gear... the one attached to the pump does not wear, its the one that drives that up in the cam cavity (unfortunately). Look here: http://badweatherbikers.com/buell/messages/3842/14 7988.html?1127519856 Where I snagged pictures from other people. Was that sportyeric that took those originally? I forget. Anyway, that shows the inside of the cam with a stripped gear. Then hit this link: http://www.badweatherbikers.com/cgibin/discus/show .cgi?tpc=3842&post=518828#POST518828 Where I posted a picture of what you can see as you look up through the hole the oil pump used to occupy. Thats what your inspection will look like... In hindsight, that gear probably had quite a bit of life left in it, but I replaced it anyway. The job is hard on one hand, easy on the other. Its amazing how many bits and bolts and pieces come apart to remove the rocker boxes, and rotating the engine forward feels like there are a million steps to do, but then you look up at the clock and see you got most of it apart in about an hour. | ||
| Reepicheep |
Oh, and the bronze is only better then the stocker if the stocker has a problem. I think there is some tolerance stack on the machining of the oil pump mating surface on the cases. Some bikes eat gears, some have no problem. Have not looked at the 08 oil pump configuration, but I bet it makes it a moot point and solves the problem once and for all. | ||
| Mikej |
I thought there were some other changes to the pump designs, not sure if a newer pump is a direct bolt-in replacement. Somewhere on the site here is a write-up of someone's who had access to a nice machine shop and they surfaced and realigned their oil pump mating face to bring the pump mounted gear into better or proper alignment with the cam gear. I'm thinking of re-camming the S2 and will be looking into this very closely. Might have to find someone with a machine shop to help make adjustments. (off to search the archives for oil pump recommendations while I'm thinking about it....) | ||
| Kyrocket |
O.K. Reep it seems you are overly qualified to answer this, especially after seeing the pics. This is my situation, '99 X1 23k miles and has been very trouble free. Owned since new and all oil changes and so forth. I am going to check it anyways but what do you think about changing the gear? I know it ultimately depends on what it looks like but is there a "magic" number where they start to detonate? This bike has led a fairly mild life, I rode the piss out of it until I had kids then the road time went downhill. It's only been on one tire twice, both times on accident but usually sees triple digits 9 out of the 10 times I ride, if just for a brief period. Let me ask you this, can it be changed without dropping the pump? I know it sounds like a stupid question but I try to stay away from that side of the engine. I've done the rocker boxes so I'm slightly mechanically inclined and I own a service manual. Picked it up for $5 from a girl in Florida, couldn't pass that up. Thanks for your help. | ||
| Reepicheep |
You are stuck on that side of the engine regardless. To replace the pump, you have to pull the cam cover. Pull the two bolts for the oil pump (when you need an oil change anyway), drop it out, peek up there and see if the gear is worn, and proceed from there. If it's worn, the cam cover has to come off, which means the rocker boxes have to be loosened. Unless you have collapsible pushrods or something. I had a dealer mechanic tell me its possible to remove and reinstall the cam cover with the rocker boxes in place, but it is highly likely to damage the cam bearings, if you can do it at all. If you inspect it and find the gear is not badly worn, I would not mess with it. Put the oil pump back, finish your oil change, and keep riding. That writeup was whitebuell (or something like that). He posted a followup that showed the problem was solved. The error was in the machining of the cases, but he solved it be machining a complementary error into the oil pump, which lined everything up again. | ||
| Sloppy |
I just recently replaced my oil pump drive gear and the damage that it appeared to have through the oil pump "window" was far worse than it actually was. Mine showed bright wear points on 3 flutes. But once I took it out it turns out that was the ONLY wear on the gear. Our local mechanic says that he only sees significant wear on bikes that are frequently drag launched. It's fairly easy to replace as long as you have a clean work area. You only need to remove the rear valve cover to have access to the cam gear cover, but it's quite simple to do as long as you're organized. The other tricky part is to re-set static timing without the "break out" box. So I'd recommend that you inspect regularly (every 10,000 miles) and once you see significant wear (if you ever do), then you can replace. I've got PN's you'll need if you'd like to do the job. | ||
| Reepicheep |
Great points Sloppy... In my case, the gear looking through the hole looked much worse in place then it did after I got it out and on my desk. And your are right, if you line up one cylinder to take the load off the valve train on that one, then you can leave it alone, and just loosen the rocker box on the other. You have then removed the load from both pushrods and can easily and safely remove the cam cover. That means at least 1/3 less work on the whole project. Is there a reason you say the rear? On an XB, I wonder if you can get the front rockerbox loose without rotating the engine forward? Or would the exhaust header be in the way, meaning you have to rotate the engine anyway... Static timing on the XB was easy... pull the timing mark plug, rotate the rear wheel by hand with the ignition on, and listen for the fuel pump to kick on. It should trigger right as the marks line up. It takes a bit of wiggling, but I think you can get it spot on. I didn't even pull the plugs (though that would have made the whole process a lot less fussy). And besides, everything in there is postively keyed off the crank, so I don't think replacing the drive gear has any effect on your timing. Probably doesn't hurt to do this to inspect your cams either. When I did this on my M2, I discovered that my drive gear was bad but not as bad as I thought, but I had a cam with a pretty serious divot... the same cam with the same divot CeeJay had on his M2 interestingly. | ||
| Bombardier |
Reep, I read that the 08 pump is a geo-rotor design although I am not sure where it is driven from. | ||
| Sloppy |
Reepy: Rear jug cam on an XL needs to be removed to get to the oil pump drive gear so that's the one I wanted to remove the spring load from. Also there's alot more clearance to get to the the rear jug than the front. On an XL it was just quicker via the rear than the front. Don't know about the XB series though. Didn't know about the static timing procedure on the XB. For the XL the FSM says to go to TDC, get into the ECM to get the right input volatge to set timing. To get to the cams you have to remove the ignition pickup. You scribe the plate to get close upon reassembly, but you should check in case the cams turned while you were replacing them. | ||
| Reepicheep |
It's all coming back to me now. I *did* have to set the timing, didn't I  I guess thats why people should follow the factory manual and not internet postings..... ;) Makes perfect sense about the rear jug as well... You can do the ecm "wire in an LED and look for the light" on an XB, but you don't have too, as the fuel pump kicks in at TDC and gives you an audio indicator. Not perfect, but neither is trying to wiggle that timing plate... a little bit goes a LONG way. | ||
| Al_lighton |
Jason, The pre-08 bikes had the engine side and scavenge side gerotors (see http://upload.wikimedia.org/wikipedia/commons/thum b/d/de/Gerotor_anm.gif/180px-Gerotor_anm.gif) stacked on a common shaft in the oil pump, driven by a crossed helical gear set off the pinion shaft. The Oil pump drive gear and pinion gear share the same key. Crossed helix gears can only transmit limited power due to point loading in the gear mates, and can have high wear when not perfectly aligned in higher power transmission applications. The 08 oil pump puts the engine side gerotor on the end of the # 3 cam, and the scavenge side on the end of the #4 cam. Might be the other way around, not sure. But the big deal is that they are direct driven off the end of the cam, that is, they plug onto the end of the cam like you put a socket on an extension. So other than the higher load on the cam spur gears, there is nothing like the old oil pump drive gear to wear. The other cool thing about the 08 design is that the cams are hollow, and the cam journals are parent material pressure fed bores. Since the gerotors are in the end of the cam cover, it was fairly easy to route the oil from the pump into the cam ends. The pre-08s used splash fed brass bushings that had to be precision reamed. The 08 design is so much better than the previous design. | ||
| Mikej |
So this then begs the question, can an older Buell ( 1995-2002 ) be upgraded to a 2008 type system? | ||
| Blake |
The gearcase and oiling system is too different, so no, unfortunately not. | ||
| Mikej |
Okay, thanks, just playing with ideas. |
