Cam re profile.

[Laverdaroo]

Evening peeps,
As most of you know the bike's in bits again and whilst the lids off I thought it might be a good wheeze to get the cam reprofiled to allow a bit more duration both in and out to improve what midrange there is and basically be a faster bike than Phil's just so I have the mental edge, yer know

Anyway, has anybody had this done and if so where at and at what bonkers cost was it? AND, was it any good post op?

I've sent a message to Newman's but whilst chatting to a few on here a discussion was mentioned with reccomendations and I can remember the thread but cant find it Any avice chap's and chapess's'sss?

[SteveW]

I’m about to put in a CB650 cam in my 550, supposed to be a nice performance upgrade.

[Nurse Julie]

John Webley has a Newman Cam in his CB500/4

[Sesman]

“Faster than Phil’s”….my arse.  Go for the CB650 profile…£100 quid or so regrind…. Best contribution is the inlets Roo. Port matching and raising the inlet roof and casting removal will achieve the best results. Frankly though, don’t bother.

[Laverdaroo]

Cheers all. Yer reckon Phil, or are you scared I'll smoke yer ? Yeah, right

 I'm interested to see how Steve gets on after his 650  cam install mind? Steve, have you done al the porting required as well or just gone for the cam etc.?I have nothing tho guage against as I've never ridden one but my cam is deffo showing its age and a freshen up wouldnt hurt tbh. If its gonna get a refurb, if poss, I might as well try to get a bot more out of it if material has to be put on, ground off, whatever.

Just a thought ......

[SteveW]

Just going for the cam at the moment.

[Sesman]

Boys are back in town,,,,

[Laverdaroo]

 

[Sesman]

Steve. I’m sure you will have noticed, but check the inlet stubs where they meet the head. I couldn’t believe the overlap (step) on mine.  I’m pretty sure doing a quick and dirty matching exercise would be worthwhile.

Roo, Newman is definitely a good shout as not only will he re-profile , but he’ll case harden too.

[Sesman]

I was just wondering, will it also be necessary to have the rocker faces cleaned up too?

[Bryanj]

I dont think the cams are hardened as the rockers are

[mickwinf]

I bought a spare engine for Lazarus which included a 650 cam and modded head. The previous owner was a bike mechanic and smoothed and ported the head and inlet ports. The 650 cam may foul the head so some metal has been removed to clear. I have used the head but not the camshaft as I heard there is some problem with the tachometer drive being different?

[SteveW]

Info here:

http://www.chinonthetank.com/2016/05/cb650-cam-in-a-cb550/

[McCabe-Thiele (Ted)]

I've used Piper cams in the past in Mini A series engines tbh in the early days they were not as good as BL Special Tuning parts but improved over the decades. Iirc the case hardening was an issue they sorted. The sporty ones used to cause issues with rocker shaft wear due to the extra load from the profiles.

[Johnwebley]

John Webley has a Newman Cam in his CB500/4

 I bought a SH cam to use as doner,,
asked Newmans for a "fast" road profile,something to  increase the grunt above 6K.

 it has been succesfull,

  the bottom end is still sweet like a pussycat,but as the revs rise it feels better,during normal journeys it breaths better ,cruising between 5 and 6k on less throttle,good fuel economy,60+ to the gallon,

 made over taking in 3rd  much better,romps up to 9k,

 cost about £160