R Kit Instructions

Post by **huskyracer** » 18 May 2005 07:10 pm

Maybe the idle mixture (with choke off) is sooo lean, that you have the throttle to far open, so when you pull the choke out, you give it the right-ish mixture, and off it races to 3-3500 rpm, maybe worth closing the throttle stops down a bit? thinking about it, somthing must be going on, as I dont think the choke circuit would ever have been designed to raise the revs that much.

Post by **foggyjames** » 18 May 2005 07:33 pm

That's the thing - (as far as I can tell) the throttles won't close any more than they already are - the adjustment screw is set to where the arm stops (if you remove the screw), and they look (although it's hard to tell, as a very minor gap is enough) like they're closed.

Or have I got you wrong...are you suggesting that the idle screw are wound in so far that the idle circuit is just acting like an air duct, waiting to be richened up by the 'choke' circuit, effectively creating a partially open throttle? That would kinda make sense, although the mixture screws are just fuel metering screws, so I'd be surprised if that's possible. The balance tappings are all screwed in (sealed), so it's not that.

Would pictures of the enrichment circuit (in various states of disassembly) be helpful? I'll also go leak-hunting with a can of carb cleaner.

cheers

James

Post by **quentin** » 20 May 2005 07:26 am

foggyjames wrote:Quentin - THANKS!! That's EXACTLY what I need.

Just one thing - I think page two of the manual didn't upload correctly.

cheers

James

Ok, it's fixed now.

I'll scan some more documents this week end.

Post by **foggyjames** » 20 May 2005 01:12 pm

Excellent - thanks!

My latest theory on the carbs is that the enrichment circuit DOES feed in extra air - the 'arms' on the top do not seal too well (by design), and you can hear air rushing in (me being a bit slow!). My plan to test this is to wind the idle mixture screws right out (rich), then push the 'choke' in...

cheers

James

Post by **foggyjames** » 20 May 2005 04:18 pm

Latest update: I've wound the mixture screws right out (they're now loose!), and it idles (by ear, in terms of mixture) correctly without any enrichment. That's not right - they ought to be ~3 turns out, so I clearly need enlarged idle jets. It works though

However, the throttles now try to creep open, and even when you press them shut manually, it still wants to sit at 2000-2500. I've got around this by incorrectly balancing them (ie: between the carbs), so it idles (with added vibration) at ~1500. Next job is to check for more vac leaks.

We're getting somewhere anyway - not least that I now get a sensible reading on my vacuum gauge!

cheers

James

Post by **foggyjames** » 20 May 2005 05:47 pm

"Hello, my name's James, and my mummy says I'm special"

I've just been having a tinker, and re-reading the instructions Iain (Huskyracer) sent me in a PM. I think I've figured out what's going on.

What I thought was a 'throttle balance' screw is, as Iain put it, the idle speed screw for the carb not directly connected to the linkage. It's like a master and slave arrangement. What's been happening is this slave carb has been set too far open, while the master has been set back shut (as I've mentioned several times). The 3500 rpm idle has been coming purely from the slave carb. I can only assume it feels smoother this way around due either to the extra air correcting a mixture inbalance, or just that the extra revs have smoothed it out.

So, the plan of action is to crank this carb back even further to get the 'correct' idle speed, and then start adjusting the idle mixture screws precisely! It feels like I'm getting somewhere

The current set-up is live-able with for a week or two - no choke on idle, then half choke to accelerate!

cheers

James