Wet trackday and HRC carbs

[28hodge]

So I'm looking at booking a trackday in feb at oulton, I did my first trackday down there last year in the middle of feb and it was really wet and very cold, still lots of fun though. I was running a stock carb set up that day and other than forgetting to connect the dry break connection on the fuel line in the first session ran all day no bother, done a couple trackdays since then but all with stock carbs, again no issues.

However I'm now running a full HRC carb set up (NC30) complete with fibreglass air tray under the carbs, just a bit curious if I need to protect the open carbs from any spray and water that may manage to make its way into the carb area under the front yokes?

I've got my complete original carbs to hand so can replace them if that's better for a wet day, but not ridden with the HRC setup so would like to give the a run to see how they are but if it's a bad idea in the wet then I won't bother.

Anybody got any advice as I've ummed and arrrd over what to do for the last couple days and not really got very far!!

[CMSMJ1]

I reckon you should be OK...but you could always get something to catch the spray - I assume you have some mesh to stop stones and gravel getting eaten anyways? That should stop floods of water getting in.

My open RVF carbs on the road bike never suffered..but there was at least a slim filter in there.

[Drunkn Munky]

Unless your prepared to fiddle about all day I'd be tempted to run your stock known working setup, they may work straight out of the box but it's unlikely. If conditions are reasonable it could be a oppotunity to get them dialed in if it's raining then you got enough going on.

Post the carb setup, maybe someone else that's running hrc carbs can post there's so you have a base setup.

As mark says I wouldn't worry about spray, I've run in the rain with open carbs and a air feed from under the yokes, never gave any problems.

[28hodge]

That's sound thanks for the advice, I am still to fabricate the mesh mark but yes it will be getting some over the carb tray prior to any trackday.

I had considered just putting the standard carbs back on so that like you say I can just have a hassle free day, but would like to try and get a setting on HRC carbs, I'm kinda hoping I can get it to the dyno prior to the day which will help.

I'm over in Norway at the minute visiting the other halfs family, but I have the settings written down so will post my base setting up when I return to the land of rain!!

[lukemillar]

I have raced in the wet with the HRC carb setup and haven't had any hassles so I wouldn't worry! I have had more hassles with spray from the the rear wheel getting into the electrics than any water through the intake

[28hodge]

Ok back home in plus temps, got to minus 13 in Norway which felt a little chilly!

Current spec of the carbs are as follows
Rear cylinders

Pilot 40
Emulsion 5 hole
Main 147.50
Needle 8zf
1mm washer

Front

Pilot 40
Emulsion 4 hole
Main 145
Needle 8zf
1mm washer

Haven't managed to make a note of the air screw/mixture screw setting, but I've had it running with these on and it idles well and the revs don't really hang, it used to run with 120's rear and 122.5 fronts with adjustable needles standard pilots, it's been ported and runs a full 4-1 micron system!

Any advance on the above Hrc carb settings?

Luke my cdi is wrapped up in Sandwhich bags, tho they are only asda Sandwhich bags not the full fat Hrc ones only had one really wet trackday but never had a problem with wet electrics.

[Cammo]

That sounds about right, if anything it might be a tad rich but safer that way than too lean. I'm assuming you have the hrc velocity stacks for this to run properly.

I never had any dramas racing in the wet with the open carb setup.

[marcus57]

Looks like those are the settings I will build my carbs to and go from there

[28hodge]

yeah they have ricks reproduction hrc stacks on them and RCJ's drilled carb tray plus the fibreglass airtray under the carbs.

im thinking they are going to run rich and stumble around 6-8k, still hoping i can get them on the dyno to refine them a little prior to a trackday

[Cammo]

I personally wouldn't bother with a dyno, you'll end up making lots of small changes which might not relate to any different feeling on track. Just take it to the track and see how it runs.

A midrange stumble won't hurt on the track, just keep it above 8000 revs!