Fuel Pumps on Ebay

[Dave Ditner]

I published an article in the Xpress awhile ago on the hard starting problem, and [/b]the fix is easy, and cheap (about $5.00)

First understand the reason that hard starting occurs. It's called the vacuum shut off valve. It can be disabled by taking it apart and reversing the diaphram and spring, but if you want it to remain functional you do that as well, assuming the valve works. Trace the vent line to the diaphram and you'll see it ends down by the center stand pivot on the right hand side of the bike behind the clutch housing. Remove the line from it's lower clamp and bring it up behind the RH side cover. Go to the nearest medical supply store and buy a replacement bulb for a blood pressure cuff. Stop at a parts store and get a plastic vacuum fitting that will fit into the bulb on one end (mine was 1//4") and have a 1/8" nipple on the other. Plug it into the end of the hose and apply a little pressure. YOU may have to cut the vent hose back a little to get rid of the breaks and cuts that can happen to the botom of it. Once you get it where it will hold pressure, apply some and hold it for a couple of minutes. Pressure on the vent side of the diaphram is like vacuum on the working side and while you're squeezing the bulb, fuel will be flowing. After applyng presssure for a couple of minutes, remove the bulb, reinstall the side cover and fire it up. All it will take is a few twists of the throttle. Your starter will love you.



Dave Ditner, Tech Editor.

[Robert Hill]

I know this is a way late reply, but being new to the site!

All you goota do is bypass the stupid vacuum feature of the petcock.

Then, when you turn on the valve, fuel flows. PRESTO!

Fashion a new piece to replace the vacuum valve under the tank. I used

brass fittings and teflon tape. I also installed a PINGEL fuel valve. This

thing flows the gas, man! Your bike will fire instantly, everytime.

Robert Hill

Oklahoma City

[broook]

And as always, remember to turn off the gas tap especially if left on the sidestand. That way the #1 cylinder will not fill with gas if the float valve passes.

[Terry]

I'm wondering if that advice is for the early models only or for the Prolinks too? Now that I have an 82, I was told by the previous owner that he never turned the fuel off and never had any problem. True?

[Carl]

Vacuum off the engine controls the petcock. No vacuum....no fuel through the petcock

[broook]

This all started with the 79 model that was made with no vacuum control and a lot of people had flooding problems, so for the 80-82 models Honda put the vacuum control on and caused another problem for most owners by creating hard starting. Most of us remove the thing altogether and replace it with a $2-00 plastic Tee joiner. If the bike starts OK with it on, leave well enough alone. You are one of the lucky ones.

[Randakk]

I'm not a CBX expert but I doubt that an electric fuel pump is necessary on CBXs.



However, you may be interested to know about something I discovered on this topic in my work as a Honda GL1000 restorer. See: www.randakks.com



The GL1000 has a mechanical fuel pump since the fuel tank is under the seat. These pumps are no longer offerred by Honda, so I recently engineered an electric fuel pump conversion. These are obviously not appropriate for show bikes. I designed this mainly to keep "runners" on the road.



There were 2 happy side effects:



1. idle improvment due to steadier fuel pressure at idle (no pulses as with the mechanical pump).



2. Instant starts after short lay-ups. Most carbureted bikes suffer from this problem due to evaporation of the fuel from the float bowls. The problem is especially bad on GL1000s since there is normally no fuel flow unless the engine is turning due to the mechanical fuel pump set-up (even if the non-vacuum petcock is "on").



More details here: http://www.randakks.com/Electrical%20Parts.htm#2



and here: http://www.randakks.com/TechTips.htm#12



and here:



http://www.randakks.com/Randakk's%20End ... pecial.htm



Incidently, I bought RC003 from Mike Barone in November.



I agreee with Dave Ditner above regarding vacuum petcocks. I despise them! In fact, all the bikes in my stable that ever had a vacuum petcock quickly got a mechanical petcock conversion.



P.S. Why I am listed as a "Moderator" after only 3 posts? You guys are generous (or have low standards!)

Regards,

[real6]

Randall, you are such a wealth of good information that they probably should elevate you to some form of deity status! I personally apreciate technical information, along with passion for motorcycles themselves and attention to detail...all of which you share with us. I've only ridded a GW once, maybe a late 70s and don't remember much about it other than it was akward looking at, but once in the saddle it was fine. Please please come around and share your information and passion with us here on this site more often!

[retrex]

My .02, In addition to the X, I have a couple of Suzuki GS1100s with vacuum petcocks. The Suzuki solution to no vacuum no fuel after sitting idle a long time was to have a prime function built into the petcock to overcome no fuel. What they did was when the petcock was put into prime position a little pin would push the diaphragm open to let fuel freely flow to the bowls. Once started the petcock was put into run mode and the normal vacuum took over. Now I don't know if this is feasible, or even necessary in view of what I am reading here, but it would seem that you could run a valved bypass that takes a line from the petcock and splits it before the vaccum and then reintegrates it after the vacuum. On the non vacuum loop a stop valve is installed in line to bypass the vacuum loop and feed fuel directly to the bowls. When starting open the valve, once started close the valve. Also a nice backup for your vacuum diaphragm going on you out in the boonies. BTW I have a Pingle.

[Mike Nixon]

Just a note on the electric fuel pump. A few years back I met a fellow at a CBX rally that added an electric fuel pump to his X. He said it immediately improved his difficult starting problems. Having read over the years about people priming the carbs with various devices to get fuel to cyl. X and so on it seemed a good idea. The next morning when we were all getting ready for a group ride there was the usual sounds of starters doing their starting thing, people twisting the throttle and repeating the process as the bikes came to life. There was one exception, the fellow with the fuel pump. He turned the key pressed the starter and the bike came to life immediately. The claims on ebay are over stated to be sure however I know 30 people including me who will tell you don't be so sure on the cold starting benefit. Life is good, enjoy!!!!

Rich Pleines

Ditto. There is a long history of CBX owners adding fuel pumps to their machines to aid in quicker starts. Don't know why, Jim, you have never heard of it. As to all the claims on eBay, well...that's another matter. :)