I had the misfortune of having to ride a HD Sportster today.
Can't say I enjoyed much but the first thing I noticed was how quite the engine is. My Buell sounded like a box of spanners in comparison. Seeing as its roughly based on the same engine why do they make so much mechanical noise. Thoughts?

Quite what exactly?
Quite loud?
Or quite quiet?

_________________
'98 M2 Razorback, it's a keeper.

You've probably got a very loud Nigerian Prince hiding in the top end.....

_________________
I started out with nothing and still got most of it left.

typing on an iPhone without my glasses

I've been living abroad to long. quiet !!

rubber mounts??

_________________
Buell X1
Buell xb12s
Buell 1125r
Ebr 1190rx
Bimota Db7
Norton v4rr??



http://www.aph-performance-engineering.com

No, it's mechanical noise not vibration?

Your Buell is fucked

_________________
2001 X1 2009 1125CR 2006 Uly X3 2010 Uly a fully Maz'd S1 and a 1991 RS1200 Westwind.

I believe the XB cams result in a lot higher valvetrain noise than the lower lift cams...

http://www.nrhsperformance.com/tech_eca ... cams.shtml



My .536s are noisier than my .497s (S1/S3/M2/X1) and a standard sportster has a lower lift than that...

_________________
08 Specialized Langster

Pash, what else did you fit along with the 536's ?........hydrasolids, roller rockers, uprated springs, etc. etc. ??

_________________
Mithered ta death.
92 MB
96 S2T
98 S1W
00 M2
01 X1
03 P3
10 CR

Nowt...

I have XB heads and rocker boxes, which were designed around the .551s. These are shorter duration and higher lift than the .497s in the tubers, hence higher acceleration during operation (hence the noise), and to combat valve bounce with this and the higher engine speed of the 9, they lightened the valve train; thinner valve stems and behive spings (and only one of them).

The .536s have not only a longer duration, but a lower lift than the .551s, which reduces the acceleration of the valve train two fold and means the XB heads and rocker boxes are still overkill with these cams. As you know, the drawback of these cams is the exhaust valve lift at TDC (over 20% more than the standard tuber cams), hence the need to cut into the valve pockets...

_________________
08 Specialized Langster

So does the XB9 make more noise than a 12?. I assume the the 9`s valves have a higher lift?

Suppose there`s not much you can do to cut down on the valve train noise, except wear earplugs, which I do.

Both models share the same E-cams, so lift should be identical.

_________________
"It is often said that before you die your life passes before your eyes. It is in fact true. It's called living."
Terry Pratchett

Can I just say Past that makes a lot of sense