Technical page
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Sportster battery support can fracture oil tank.  Aparanetly a common problem with Sportster models is that the battery carrier is welded on the inside of the oil tank and vibration coupled with the weight of the battery fractures this weld, allowing oil to weep out.

When I bought my 1200 Sporty new, I read a tip that suggested using a rubber exhaust bobbin under the outside front of the battery carrier, fitted in such a way as to transfer some of the weight onto the engine clutch casing, via the rubber bobbin.  Well I did this and after 7,000 miles I had a fractured weld and leaking mist of oil all the same!

So I guess it's just something to be aware of - unless anyone out there has a tip that works?

Sportster rocker box gasket leak.  My Sporty started to leak around the rocker box gasket and so have several other owners I talked to had the same problem.  Anyone know why & how to fix it permanently?

Avon Venom tyres from Watling tyres in Catford.  I have just replaced the tyres on my Dyna and had Watling Tyres in Catford fit Avon Venoms for a ride-in-ride-out fitted price of £155 for both front and back tyres.  Two Harley dealers quoted me £150 just to supply a rear (Harley / Dunlop) tyre plus about £50-£60 fitting.  And they couldn't fit me in for weeks while Watling did it the same day.  So far my Avons are a real delight (more rounded profile than the Dunlops) and the confidence they give me have me grounding my heels more than before.

Anyone got any tips on different tyres they've tried - good and bad?

What Horsepower? Anyone who has in any way tuned their engine must wonder what real extra power they're getting.  I put my bike on a Dynojet model 150 Dynamometer at Minehead and got a reading of 58.7 SAE corrected horsepower at the back wheel.  For the technically minded, the air temperature was 14.4 degrees C and air pressure 970.5-15 mBar.

I would love to know where the power surge at 75 Kmph came from in third gear.  Anyway this is an Evo 1340 engine with Kuryakyn hypercharger, dyno-jet kit, race cam and valve springs plus the Vance & Hines Big Shot exhaust.  A useful site about tuning and what to expect is NightRider.com

And how about the Kwak then? 
After HM Racing, Orpington set-up the bike, it makes 116 hp at the back wheel. I think this must be a pretty good result after fitting the Blueflame full system (stainless steel header plus titanium tri-oval road legal end can), as this output is with an otherwise standard bike, except the air filter is now a K&N and especially as the can is in full road legal mode i.e. all baffles in place.

HM and indeed another racing specialist advised against fitting a DynoJet kit to the ZX-7R, preferring to get the right fuelling by re-jetting. Looking at the Dyno graph, the power on standard carb setup was already up to 113 hp (I think most bike magazine tests of the standard bike come out at about 108 hp – so already a 5 hp gain). So the set-up added another 3 hp overall – and look at the massive improvement in the “flat spot” between 9,000 and 11,000 rpm – looks like a 10 hp straightening of the dip at this important point.

So basically twice the BhaitchP at the rear rubber over the HOG - and probably a bit lighter too?