Need some experienced info on tuning CR Special carbs

[Warp11XX]

Any folks here have any experience to share tuning CR Specials on DOHC, air cooled, Honda motors? I guess any tuning experience would help since I'm totally lost right now. :shock: :? Put CR 33's on 1123 Wiseco kit, stock cams, but custom head...bumped compression a bit. I've got 118 mains, 58 slow jets, yy9 needles set at clip 4 from top...tried 3, no difference. Air screw out .5 turn is "best"...more makes motor die, less gets rougher idle. Will not take throttle on startup and starts hard, won't allow any choke. Once idling, will not take throttle whack, bogs and dies...can feather into throttle and seems to take off to top of tach at about 4K to 5K rpm. Is this symptom too much or not enough fuel on bottom? Haven't put filters on yet so I just need to get in a real running range to tune.

[Warp11XX]

Dayyum! :roll: I had no idea that so many folks bought an XX as their first bike. The limitless breadth and depth of knowledge here is amazing...

[porterb123]

I had an 1100F with a weisco 1123 kit and did alot of tuning with the stock CV carbs...even installed an O2 bung and heated bosch sensor and autometer AF ratio gauge. Before final tuning it dyno'd at 112 hp.

There is an excellent site but it seems to be down right now.

www.cb1100f.net.

Martin there has run and installed CR's and there are quite a few mechanics/ racers there

Try them out when the site is back up.

Porter

[porterb123]

If I had to guess, it sounds rich...do the CR's have adjustable floats, if so have you set them...are the air/fuel screws on the inlet side of the carbs or the outlet...engine side. Air screws on the inlet side richen up as you turn them in...on the outlet side turning them out richens. You said it would run up to 4 to 5K. Try riding at that speed and giving it a little choke...if it cuts out....you are too rich. If it picks up, your too lean.

How much do you know about carb tuning???

Porter

[Warp11XX]

I'm Quik900F over on Glenn's board...one of the earliest members...site was 2 days old when I joined. I know quite a bit about CV tuning from running them for almost 15 years. I always had good luck with my Mikuni's on my Z1 too...CR's are totally new to me though.

The air screws are on the intake side of the carb...I also tried changing the needle height to richen by one clip but can't tell any difference. I've got the Keihin troubleshooting guide and short manual but no real solid reference to this particular problem is covered. Sudco/Keihin lists the yy8 needle as stock part for my application...yy9 is leaner...correct? It won't accept any choke without dropping revs and dying immediately. Seems even harder to start after that....I'm gonna try leaning needle by dropping down this evening and see what happens. Should the needle really have that much effect prior to midrange rpm? Slow jet is spot on for my application by handbook reference...I'm befuzzled... :? I don't think floats have adjustment tab but I'll confirm that this evening also.

If you need on the F board, you can get in the temporary/test site at cb900f.net until the server issues get straightened out. Not many folks have found it yet...I posted over there first of course but nobody home... :roll:

[porterb123]

I've seen a few of your posts. I visit occasionally. I was there on the old forum, before the new about 3 years back. Do you remember Rays DOHC message board...He was the long time Honda mechanic in Cali...thats the board I started on first. My name was the same over there...I sold my F to BiSexual Britney.

Still sounds rich. Either the floats are set too high...closer to the flange or stuck open and letting it flood or the pilots are too big. The needles should more affect midrange with the throttle opened more than 1/4 or so.

Run it at 4 to 5K and hit the kill switch and pull the plugs and see what they look like. When the bike is lean it will kinda surge and pop back through the exhaust when you close the throttle.

Let me know how it turns out

Porter

[Warp11XX]

Yep I remember Ray's board. It was still up until just a little while back but retired I think. Still has an archive page up though I think.

Britney has bumped in once in awhile...she dropped us some pics (that I crossposted here :twisted: ) and told us they were going in June? Penthouse...haven't heard any more about it and nobody saw her published. :roll: Dunno...maybe it just didn't work out with the publisher.

Anyway...I can't get it to take throttle up too 4-5K...I have to feather into it to get it to climb. From about 5 it will take off like a banshee... :roll: I'll play arouind somemore and see what happens. Thanks for the tips though! Every little bit helps.