XBR RESTRICTION

[LANCELOT]

Hi folks
Question from a newby, could any one tell me how the xbr500 is restricted? I bought the bike in september last year after being stood for 10 years, it has a genuine 16,500 miles on the clock and after recomissioning it I am very happy with it apart from the restriction issue, to be fair I was informed of this when i purchased it.
I have scoured the interwebb for info but cant find much apart from it could be a different inlet manifold (ie bore size) or it could be a different throttle linkage on the carb.
Look forward to the reply's
Regards,
LANCELOT

[SteveC#222]

I assume it's one of the restricted German versions?

I think it's restricted in the carb ( and possibly the cam). There are a couple of articles on one of the German sites.

Use Google to search for www.xbr.de. It will be bring it up with the option of Translate. On the translated version , in the left hand column go to 'Techntest' click on this then scroll down to 'info' and there are two articles there that might help.

I've just checked the parts catalogue and  there are 2 German designations 'G' and '2G' - I think the 2G is the restricted version (25bhp?) and there is a different camshaft code for that. looks like different carb bits too.  Might be a difficult job.

[SteveC#222]

Having had another thought if it's a UK model restricted to 33BHP - I hadn't thought of that as the standard XBR is only about 33-35 bhp at the back wheel anyway..  If it's a UK model then I would look for a restriction washer in the exhaust ports/downpipes first ( they're easier to get at) then I'd check the inlet manifold/airfilter. It wouldn't take much to restrict a UK bike.

[LANCELOT]

Thank's Steve,
The german site is a mine of information, looked on the wikki page and checked engine and frame Nos and my bike is the 44bhp version, maybe I was expecting too much from the bike as I said I am pleased with it.
Performance is ok and it is fine cruising at around 60-65mph but I have watched you tube vids of xbr's showing the clocks and at 70mph they are running at 5000rpm, at 70 mine is running at 5500rpm approx.
Does this indicate it is in fact restricted, discuss.

[tj63]

It more likely indicates that either yours or the one in the video has had its gearing changed.

44bhp isn't going to blow your socks off - I know as my thumper's got 48 and my socks are still on!


Trevor

[SteveC#222]

It's never going to go like a 4 cylinder sports bike, but they are reasonably quick for a 500 single. Don't be afraid to give it some revs, there is a nice little kick at around 6000rpm. Although Honda quote 44bhp ( at the crank) most standard bikes that have been Dyno'd only put out 33-35 bhp at the rear wheel. With these bikes it all about l;earning to keep the power on through the bends, in good hands they can embarrass a lot of bigger bikes through the twisties!

[LANCELOT]

Thanks Guys, I think it's ride and enjoy then, many thank's for input.
Safe riding,
Lancelot