| Author | Message | ||
     Jerome |
Hello everyone, Owning an European M2 model-year 2000, I enjoy the very popular Lightning cams mounted stock for the european market. But now I'd like to get more grind at low rpm from my beloved Buell, even if this means less arm stretching at high revs. Question 1 : would a switch from Lightning to Sportster cams be sufficient to get this big torque at low rpm ? Question 2 : having the race header on my M2, would another choice of cams be better or should I also put back a stock header ? In the latter case, should it be a 2.5" or a 2" header for maximum torque ? Question 3 : is there a reference that should be preferred for the Sportster cams mounted on M2 ? An improvement with a given model-year ? Deep thanks in advance for sharing your knowledge. All the best, Jérôme | ||
| Phat_j |
i think your best bet, and probably least expensive is to just change the pully... you should have a 55 tooth rear pully, and in the states we have 62 i belive...if your interested, i have one that i'd be willing to trade.... ping me... | ||
| Jerome |
Thanks Phat_j, but my M2 is already in full US gearing (27 x 61). It made a good improvement in terms of handling on curvy roads (not so necessary to change through gears as before with the european 29 x 55) but it did not change the way the engine expresses itself with rpm. I'd like to have it more responsive between 2.5 and 4 K, where I spend much of my riding time. | ||
| Tdshepard |
http://www.motorcycle.com/mo/mcbuell/mcphotos/m2-1.gif http://www.motorcycle.com/mo/mcbuell/mcphotos/m2-2.gif These graphs show the difference between cams on a 1997 M2 and S1. It would have lightning heads and make less torque and horsepower than your M2 with thunderstorm heads. This comparison is valid only with stock bikes, a Lightning cam bike will show better improvements with aftermarket exhaust and intake mods.....try to search posts from Aaron on this subject. Todd | ||
| Tdshepard |
I guess you will have to copy and paste to get those links to work..... Todd | ||
| Racerx1 |
Jerome, Just my opinion, but i don't think it would be worth your time putting sportster 'D' cams in your M2 if you already have the race header and lightning 'B' cams. The 'B' cams make more torque everywhere over a 'D' cam when using a race header. The big torque dip on those dyno charts with the 'B' cams is due to the muffler, not the cam. The 'D' cams have so little overlap and the centerlines are spread apart so much that the exhaust system doesn't effect them nearly as much as the much higher overlap 'B' cams. The only reason to go back to 'D' cams in my opinion is if you want to go back to a stock exhaust system and don't want a torque dip. Another option that might be attractive is to go with the 'W' cams from the sportster sport. Compared to the 'D', a little more exhaust duration, a little less intake duration, more overlap and the centerlines are closed up a little more. A good compromise between the lightning cam and the M2/Sportster cam. | ||
| Reepicheep |
Be careful which cams you get if you go with the sportster / M2 cams. They are custom fitted (to the case I think, which is probably still built on some machine that has been in service since about 1962). Different cases get different cams, which are color coded. The lightning cams are "high contact ratio", which is a nice way of saying they will fit any case. But I think they sell high contact ratio cams in the sportster grind (2002 and up I am pretty sure), direct from the factory, for like $400 a set. Aaron gave me some great help clarifying this issue about a year back, which I summarized and put in the knowledge vault. Should be easy enough to dig up if you need it. | ||
| Aaron |
I agree 100% with what RacerX1 said. One more option: advance your Lightning cams a little. If you've got access to a simple shop press, this is not difficult to do at all. I'd be glad to give some instructions. Watch the detonation. Increasing compression with earlier intake timing *can* get you into trouble. Not sure what the gas is like over there, besides expensive. Best way to do it IMO: make the motor bigger. | ||
| Jerome |
RacerX1 and Aaron, deep thanks for your input. Thus contrary to what I expected, a Lightning cam combined with the race header compares well in terms of torque output with the Sportster cams. You're probably right Aaron : I'll need to Nallinize my Buell at some point...  Thanks again. | ||
| Rattler |
<<But I think they sell high contact ratio cams in the sportster grind (2002 and up I am pretty sure), direct from the factory, for like $400 a set. >> For info, 2000 & later Sportsters...not 100% these are still in the new 04's, but I believe they are! The Sport W cams also close the intake at 19.5 degrees...not the best thing for higher compression in all cases, where they shine is what they do on the exhaust side..hence some folks get away with using them in above 9.0:1 compression...they get the exhaust heat out faster. Dale A. |
