| Author | Message | ||
     Gregg |
Bought my 2nd 2001 M2 from friend of friend. Very nice cosmetics and complete except for the unhappy engine. Was a built motor and something ugly happened in the cam area. RH crank case is damaged (bores for the cam bushings are damaged) and at least one of the valves smacked a piston. PO then sold the complete top end to someone. Crankshaft seems OK, but is suspect. I already purchased a nice set of cases and matching timing cover from a 1999 M2. Now have a contact with a salvage XB9 engine. From some research, appears one can rebuild the engine with the 1999 cases and with XB9 top end, cams, crank. Will need to modify the intake manifold to use the Keihin. Pushrod covers are completely different. Should probably put in new crank bearings. The stock XB9 engine spec shows same HP as the 2001 M2. So, down on displacement, but better flow and combustion chamber. Would set this M2 up as a touring/distance bike with an S2 fairing. Any advice/experience would be appreciated. | ||
| Upthemaiden |
There was also someone who was just selling a freshly rebuilt tuber motor. I believe he was asking $1500. Not sure what you paid for your parts and how much they're asking for the xb9 motor, but I assume if you skipped the xb motor, sold your motor and the spares you bought, and factored in the money you'd have to spend for a new front engine mount, you'd break even and save yourself the work on a motor you could just drop into your bike. http://www.badweatherbikers.com/buell/messages/21/ 822222.html?1517595793 Aside from that, yes you can put the XB cylinders/pistons/heads on your M2 motor, a few people here have done it. Just wanted to share that link with you so you can consider all the options. | ||
| Bd3 |
In regards to the touring fairing... An S2 fairing on the M2 would be difficult. On the other hand, the S3 fairing is a bolt on to the M2 with lines matching the manta gas tank.  | ||
| Phelan |
XB9 crank will not fit tuber cases without significant modifications, and the XB cams would need to be retimed and new timing cup notch cut, as the XB cams are backwards of the tubers (4,3,2,1 vs 1,2,3,4). There is no easy way of doing the cams, as most of the time the #2 pinion gear is 1/2 tooth off so it has to be pressed off and pressed back on with the adjustment, then new marks made. Chad Hart (XLXB horsepower on eBay) does this service and sells the used and re-timed XB cams affordably. Also, if you use the XB heads on a tuber, you need a custom front mount (available from Hammer Performance) to fit the different bolt pattern on the front head, and you need to drill and tap the breather bolt holes. Even if you plan to use the XB rockerboxes with PCV valves up top, you need to drill the breather bolt holes for the carb support bracket and just run solid bolts into them instead of breather bolts. If you run XB9 dome pistons on stock XB heads with retimed 551 cams on a stock tuber/Sportster crank, you will have a ton of compression (like 12:1 static). If you have 95-99 cases, you need a 91-99 Sportster or Buell crank. If you have 00-02 Buell cases, you need a 00-02 Buell or 00-03 Sportster crank for it to drop in without custom machining in the cases. (Message edited by phelan on February 05, 2018) | ||
| Gregg |
Phelan, Really appreciate the information. Going to XB9 internals may sound like a neat idea, but the reality is that this is an uphill conversion. Maybe buying a complete engine is the best way to go. Interesting about the cams and cam timing. Very good to know. Would like to find info/fotos on the actual case modifications needed to fit the later "press together" crank into the 1999 cases. Almost certain I need to replace the crank. Just a Bridgeport job for clearance? Seems that the increase in stock XB compression would not occur as long as using the XB9 (short stroke) crank. Gotta think more on that one. BTW, new to Buells and Harley engines. These are great bikes and the engine parts seem well-manufactured and finished. Castings are excellent. |
