Hoping to get some advice from other members. I've got a 1993 CBR 1000. Problem: when starting cold have to crack throttle about 20% before it will start. (Choke on full) I put a new set of plugs in and cleaned the air filter. Purchased a MotionPro carb synch tool and have a manual. I'm just not visualizing how to hook up the gauges. The manual is a Haynes and it covers 600's and 1000's. Has 16,000 miles. Thanks.

Greg

 

If it also idles kinda crappy then I'd say you're on the right track by synching the carbs. You may need a Honda manual to get a picture of where to hook the hoses. In most cases there are hoses connected to each carb (on some models there is a plug you can remove which makes it easier). You'll have to remove some of them to hook up the synch gauge. Make sure you label everything before you start so you'll know where to reconnect stuff when you're done. There is no adjustment for #1 cylinder -- you'll adjust everything to it. Make sure the bike is warm before you start and adjust the idle speed up or down as necessary.

 

THanks for the info. I am going to get a factory manual. The Haynes is too English in its verbage. Tried cross-referencing a lot of the terms they use for carb synching and wasn't able to determine what the hell they were talking about. Also, it covers a lot of models so a more specific reference would keep my confusion down. I do have a slight stumble at idle so I'm hoping this will take care of that and the startability concern.

 

To understand the Haynes Manual it helps to know the letter designation for your bike. Since it is a 1993, that should be 'P'. To check it out look on the lefthand frame tube under your seat. There should be a sticker telling what model and designation you are riding. Since mine is a 1991 model the sticker says, 'CBR1000FM'. Yours should say, 'CBR1000FP'.

The Haynes Manual says the base carb (the one to which the other three are synchronized) is carb #3, and there is a fairly good picture or diagram of where to hook the vacuum lines on your synchronization tool.

The Honda Service Manual for my bike tells how to hook up the synchronization tool, what vacuum lines to disconnect on the California model, and where the adjusting screws are located. It then says to go to the Honda Common Service Manual for detailed instructions as to how to synchronize the carbs.

At one time I found the Honda Common Service Manual on the net, but have lost the address. You might try Googling or Yahooing, whichever you prefer, for it. The one I found had only some chapters on line, but the ones I needed were there.

Good luck.

 

Tune to carb #3? Ya learn something new every day

 

The 1990-91 Honda Service Manual for Carburetor Synchronization says "For detailed instructions, refer to Section 2 of the Common Service Manual." Arggghh. It does have some good drawings showing where the rubber plugs are on the vacuum take-offs on the carbs and where the adjusting screws are. It also says that the base carb is carb No. 2. The Haynes manual gives a lot more detail on doing the synch, without referring you to the common manual.

 

For my 88, it is carb #2, since it has no adjuster. There are little black rubber caps on mine on the top front.

 

Here's the write up I did on the carb sync, with pictures.
It's not as difficult as it initially appears. The vacuum ports are on the under side of the carbs, and are actually on the intake manifold. The number four port is capped with the a plug that is unscrewed with an allen wrench. You will need to put an adapter in it to hook up your gauges. Numbers 2 and 3 are rubber caps and number 1 is the hose that supplies vacuum to the petcock.

 

i usually ignore which carb is the 'base' carb, I tune 1 and 2 to each other, then do 3 and 4..., then I synch the two pairs... remember, it's the end not the means by which you get there, as long as they're all pulling the same vacuum in the end you're good

and about the Motion Pro synch tubes.. GLUE THAT RUBBER VENT HOSE IN PLACE!... on my friends, it came off, and spilled mercury on the floor of my car.. i recovered what I could, but it's such healthy stuff I decided to leave some there.. besides now the tool is low on mercury.. VERY poor design considering it's a toxic substance, and a PITA to replace

 

Good write-up, Capt. O., on the syncro. I never knew the 93's were so much different than the previous models.