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By ChrisD
#77999
BW – yes, the roughness/bounce starts at ~4500rpm and gets worse up to ~6000rpm by which time it is awful. Maybe the bounce is only at the top end but it all feels the same to me.

NEV – yes, a typo. I went up 2 teeth from the OEM sprocket and it is only 19T. Pulls quite well, though. I was aiming for being able to cruise at ~100kph comfortably on the open road at
By NEV
#78016
Ah ok ChrisD! Yep 19T sounds better, I'm luck as mine came with a 5 speed box. Do you use new Roadrider type tyres? They are lower profile so have the effect of lowering the gearing a bit. What did you do to increase the power/torque?
By ChrisD
#78044
Gentlemen. A typo on my part. I went up 2-teeth from OEM, so I am at 19T not 21T. That gives me a GPS 70mph at 4000rpm. I cincede that maybe the roughness from 4500rpm reaching a maximum at ~6000rpm is not all valve bounce.
Actually I posted the same message 4 days ago when BW responded and although the site showed it had gone, presumably it went somewhere else.
Cheers, ChrisD
By ChrisD
#78045
Gentlemen. Apologies for the double submission.

Mr Tomshayes, I’d still like to know if you found the performance cams to have any significantly better output than the OEM ones. I too have those two sets and I am unconvinced they offer different outputs. I have asked BW to put me on the list for a set of S-cams if/when he gets any more made.

NEV, regarding my tune up, I’ve done quite a lot. 8.5:1 535cc piston, alloy barrel, larger exhaust valve, samrats, metal head joint, high capacity oil pumps, twin plugs, steel conrod and roller big-end, ace café air filter, shorty silencer (it’s a bit loud though), 32mm Amal Mk2 (on reflection I’d rather have had a 34m or even 36mm), now rebuilding after a dropped valve (see other posts). To balance all that, I’ve added a new alternator so I’ve a brighter headlamp, new shocks and brake shoes and wheel bearings so it handles better as well as one of MrH's smaller screens and indian panniers.
Cheers, ChrisD
By NEV
#78085
Hi ChrisD, thanks that's interesting, are you using modern low profile tyres with that gearing? I noticed they lower the ratio at the back wheel slightly. What alternator did you fit, was it stator & rotor? If still on AC/DC system did it blow headlight bulb?
By Tomshayes
#78091
Hi Chris

Sorry for not getting back to you sooner as been on hols for a coup,e of weeks.

I had standard cams set up as per book with no rtardation of inlet cam..Same for Hitchcocks performance cams.

I haven't had any valve bounce yet but I have got Hitchcocks performance valves and springs etc.

Regards

Tom
By Tomshayes
#78092
Hi Again

Chris D.

Yes I was doing 80 but I wasn't over revving the engine at all.. Loads of spare RPM to go but I wasn't thrashing the bike as I am still running it in.

i was feathering the throttle and it responded very nicely.

Tom
By Tomshayes
#78093
Hi Chris

I cant actually say whether the Performance Cams have given me any increase in power as I have not really gone for it yet.. As I didnt hammer it on standard cams either I don't suppose i'll really know either way unless i were to refit std cams to see if they make any difference.!

Tom
By ChrisD
#78275
Nev and Tomshayes.

Sorry for the delayed reply – I’ve been struggling with a failed laptop.

Nev, I bought the stator LU/47205 from our hosts and it performed well. I keep the headlamp on all the time on the roads and haven’t now noticed any weakening battery (at least up until the inlet valve retainer broke dropping the valve into the innards, and I’m still not back together yet). Note that I have a DC system, 1996 535cc model, so no AC headlamp.
Tyres – no low profile modern stuff. I have fitted the front and rear wheels with Dunlop K70’s (3.50”).As most of our roads out here (South Africa) are gravel, I find the ribbed front tyre wanders too much. I find that 4000rpm (from a fitted 2¾” revcounter) gives me 112kph or 70mph (from an onboard satnav) with standard gearbox gearing but with the 19T drive sprocket.


Tomshayes, thanks for your comments on the apparent lack of difference between performance and OEM cams, I too noticed that upgrade was the least valuable so far. With the performance valves I have to cut down the inlet valve guide seal by a millimeter with my trusty Dremel to clear the closing valve head+retainer! I am now fitting a NOS scrambles inlet valve (38094A) and have the larger exhaust valve (90053) both from our hosts.

Cheers, ChrisD
By ric
#78276
Image


(hopefully) Here's a dyno graph of standard RE Indian cams plotted against a set of prototypes which were then further developed and now available for many US Dollars. However the only real gains after fitment came once the ignition had been advanced to an optimum setting of 38*BTDC @ full advance. If you're still using the book setting your problem may lie there.

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