| Author | Message | ||
     Igneroid |
Can some one in the "know" tell me how many different styles of heads Buell has? And which are more desirable, performance wise. I have a 2002 Cyclone and I'm assuming the heads are Thunderstorm ones. I see some posters mention "Lightning" heads. Were these a special version used on tuber Lightnings?? | ||
| Guell |
i think the lightnings just had a different cam in them i believe. | ||
| S2pengy |
If my memory serves me correctly, the S2 used the stock Sportster heads.. In 1996 the S1 and then the S3 came with Lightening heads which had larger valves but used flat top pistons.. The S1WL was the first to have the Thundestorm heads which had even larger valves but used domed pistons... | ||
| Buellistic |
Sportster Heads, 1997 Models Lighting Heads, and 1998 Models Thunderstorm heads until the end of the TUBE FRAME Model RUN ... | ||
| Cyclonemduece |
as far as i understand your thunderstorm heads on the M2 are better than the prior lightning heads and the m2 just lacked in the cams, we have the stock stortster cams stock, upgrade to the X1 cams and you basically have a carberated lightning motor, correct. | ||
| Cyclonemduece |
as far as i understand your thunderstorm heads on the M2 are better than the prior lightning heads and the m2 just lacked in the cams, we have the stock sportster cams stock, upgrade to the X1 cams and you basically have a carbed lightning motor, correct. | ||
| Buellistic |
M2's have Sportster cams and the other Models have 1st stage Scream'n Eagle cams ... | ||
| Igneroid |
OK Thanks....so far... Does the XB heads bolt right on to a tuber of any sort or issat a completely different motor??/ Tks again | ||
| Cyclonemduece |
i think that they bolt right on | ||
| Ratbuell |
XB heads bolt right in but you need a new front motor mount, the bolt pattern is different. Al at American Sport Bike has the mounts, very nice billet pieces. | ||
| Buellistic |
"AND" you need to replace the XB small stem valves(and valve springs) with Thunderstorm large stem valves(and Scream'n Eagle valve springs) or install XB soft ramp cams ... | ||
| Igneroid |
Well, this is quite the place. Thanks for the info. I plan to eventually hot rod this motor and its good to know I've got a good start already. I don't have a link but I did find some 4 valve heads somewheres. I would imagine these would be even better flowing units. Has anyone had experience with these or ones like them? | ||
| Natexlh1000 |
I think I read somewhere that you would have to rev the engine to 8,000 to reap the benefits of having four valves. | ||
| Steveshakeshaft |
I don't have a link but I did find some 4 valve heads somewheres. I would imagine these would be even better flowing units. Has anyone had experience with these or ones like them? The set I saw ("Max T" heads IIRC) used the exhaust port studs as the the front engine mounting point. Needless to say, I was less than impressed. | ||
| Court |
Those were done by Jim Feuling. He passed away in 2002. They were never well accepted nor proven to be of overall benefit as I recall. | ||
| Natexlh1000 |
I remember those things had a plenum-style intake manifold instead of the runner-type that is normal on a Harley. I always wondered about those. I guess totally obsolete with fuel injection? | ||
| Steveshakeshaft |
I'm not sure the performance versus number of valves per cylinder has anything to do with the presence or absence of fuel injection. I believe the bore/stroke versus valve area of 2 or 4 valve heads has more to do with it. A short stroke motor will have a bigger bore area for any given capacity cylinder and will usually rev higher than a long stroke type motor as a result. The increased valve area of 4 valves will help cylinder filling in a shorter stroke motor and the smaller (lighter) valves will run much better at those higher rpm's. I do not think it so surprising really that 4 valve heads have never caught on in the Buell motors. | ||
| Chasespeed |
XB heads bolt right in but you need a new front motor mount, the bolt pattern is different. Al at American Sport Bike has the mounts, very nice billet pieces. You will need the XB pistons as well... those are different.. The XB used a completely different combustions chamber design... Flat top pistons, TIGHT quench, etc.. The thunderstorm use a 15* domed piston... wont like the heads very much Use the Xb12 pistons to keep compression the same, use XB9 pistons, to bump compression up a ways... Chase} | ||
| Phat_j |
"AND" you need to replace the XB small stem valves(and valve springs) with Thunderstorm large stem valves(and Scream'n Eagle valve springs) or install XB soft ramp cams ... that is an incorect statement.... | ||
| Alex |
Here are my information about Buell heads: The following head types were used: 1. Stock Sportster heads. 2. Heads that we call "Lightning-Heads": these are basically single plug ScreaminEagle Heads (dual plug version) which use the same valve size as the Sportster heads use but have more material in the combustion chamber pushing it to around 10:1 CR with flat top pistons. 3. Thunderstorm heads: these use bigger valves and dome pistons with a small angled squish band (combustion chamber design is pretty similar to the "Lightning-Heads" regarding shape). 4. XB heads: 7mm stems, slightly smaller valves than Thunderstorm heads, single piece beehive springs, conpletely different combustion chamber shape, flat squish area. | ||
| Rick_a |
The "soft ramp" cams were to let the motor rev to 7500 rpm in XB9's. With a 1200 there's no issues so long as you don't exceed the stock lift. There's a pretty good explanation of all the issues/benefits here. | ||
| Buellistic |
Take a hint from the XBRR ... They REV more than 7500 RPM and have the large stem valves ... Their HP/Torque is at 8K ... Believe they are being run at 9500 RPM ... "i" would not put LARGE HEAD VALVES with SMALL VALVE STEMS in my engine and be cam limited !!! In BUELLing LaFayette | ||
| Phat_j |
of course "you" wouldnt laffytaffy.... cuz your top end has never been off. | ||
| Buellistic |
Phat_j: 99,574.3 miles as of the last ride !!! THAT IS CORRECT, THE TOP END HAS NEVER BEEN OFF ... The Energizer drum is still beating and the Timex watch still ticking ... That says it "ALL" ... In BUELLing LaFayette (Message edited by buellistic on October 18, 2007) (Message edited by buellistic on October 18, 2007) (Message edited by buellistic on October 18, 2007) | ||
| Rick_a |
That's great, but the XBRR is a completely different animal altogether. It's a far cry from the typical Buell streetbike build. It also has well over .600" lift. Not everyone is out to build an 8000RPM+ 1200. A stock stroke motor would have a wasted crank in little time. A lot of folks are getting around 100hp+ with bolt-in cams and headwork. There are also valve spring kits to support higher lift/rpms for the narrow stem valves, as well. The whole idea behind the setup is less mass and better valve control with lighter springs. | ||
| Rick_a |
The problem with those heads is that these are long stroke motors and there's still a lot of valvetrain mass. I've seen a Japanese XB engined racebike as well as a European hillclimb Big Twin racer using those heads.   |
