Corrected - is the VCH carb same as VH?

[SEDoan]

I've got a VHA cam to put in a VH engine and wondering if the 289 carb is the same for both? VHA cam is slightly greater lift.

The search feature couldn't find an answer, so thank you for your expertise.
Shawn

[Simon.Gardiner]

Shawn - is that a VHA cam or a VCH cam? I've always understood that the VHA cam was the same as a VH/NH

SG

[john.mitchell]

There were two VCH''s A Trials one and a Scrambles Model. So there would be two cams.

[will_curry]

The 1953 parts list has the same carb for VH, VHA and VCH and also the same cam.

I think the above also applies to 1952 models but there were some distinctly special
VCH parts for the earlier six-stud engines.

[SEDoan]

Club spares lists the cam as "53 VCH" profile. It has a lift of approx. 0.420". The original cam has a lift of about 0.360". After asking here I called AMAL/Burlen this morning (for me) and they list the same carb for 1952 VH and VHA. Unfortunately I didn't think to ask them about a VCH carb. The difference is great enough I'd like a second opinion. Did the VCH ever use a 289 pre-monoblock?
Thank you.
Shawn
bold is corrections based on checking the parts list rather than my fallible brain.

[Simon.Gardiner]

I think that's one of the VCH cams that Pete Kemp had made.
I've got one - I'll send you a PM, Shawn.

SG

[SEDoan]

Simon, you are correct. I had remembered it as a VHA profile, but checking again shows it listed as a VCH. Ack - memory failing already! I've send you a PM.

So now the question becomes - was a 289 carb fitted to the VCH and what is the setup. Also considering running a MkI Concentric.

[SEDoan]

Corrected the title question, but I think the answer must be that the VCH was only fitted with the TT carb (is this true?). How embarrassing.

Looking to fit a 289 pre-monoblock or concentric mkI.

[Simon.Gardiner]

Shawn (responding to PM as well!)
I think that VCH profile is very similar to the HS Mk 3, it's been commented on before - I think in a thead on cam timing that almost certainly had contributions from David Anderson, but also I think Pete Collings had experience of running one (he might have also posted a profile diagram).
I've run an HS Mk 1 cam (with standard followers) in an iron head VH for a year or two, using the standard 289 carb. I don't think I changed things much. The carb was pretty well worn so probably not metering particularly accurately but the bike ran OK although probably not as well as it could have done.
The Mk 3 is a softer profile so maybe has more chance of needing less carb tuning to perform well - don't know what profile followers you're using though!
(Mk 1 concentric would be OK too, I run one at the moment with the alloy-head '56 engine and Phil Joy Mk 3 profile cam - although it seems to run out of puff above 2/3 revs; I really should have double-checked the timing marks before putting it in...)

SG

[SEDoan]

This is great Simon. The plan is to run the VCH cam in an iron VH as you are doing. I need to look through the older posts, but I believe the recommended setup was to run the HS mkIII or equivalent with an HS intake follower and a standard exhaust follower. Currently the '47 VH has a std VH single lobe cam with 2 HS followers and runs very well in the mid range. And I've not used tachometers or stop watches to correct my thinking so I'm very happy with it.