Accelerator pump rod travel

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Kool_Biker
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Re: Accelerator pump rod travel

Post by Kool_Biker »

Mike
I bow to your vast experience and include a pic of my disassembled pump, in case you can see something I don't.
P1050639 (1).jpg
For a minute I thought I had erroneously used the air cut off valve spring in the accelerator pump, which is shorter, but no such luck. It is slightly narrower so would not fit properly. And in any case, the maximum travel of the rod is set by its diaphragm end, 'bottoming' internally against the pump case (pushing on the brass valve bottom) ... it is in no way limited by the spring.

Puzzling ... :evil:
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Aris Hadjiaslanis
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Berkshire, Windsor

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Re: Accelerator pump rod travel

Post by Kool_Biker »

Help!
Anybody got a picture of the 79 Z fuel pump o-ring, preferably sitting on the no 3 carb bowl.
I have managed to mix mine with few more - and I am pretty sure the one shown here is too big reducing or even choking the output flow of the pump? :cry:
Thanks, Aris
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Aris Hadjiaslanis
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daves79x
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Re: Accelerator pump rod travel

Post by daves79x »

Your o-ring is too large. It is a pretty thin one - there is no other like it on the CBX carbs.

Dave

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Re: Accelerator pump rod travel

Post by 6Pipes »

4400

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Re: Accelerator pump rod travel

Post by 6Pipes »

4401

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Re: Accelerator pump rod travel

Post by 6Pipes »

I was having some trouble posting a pic with my narrative but shown above are a couple of shots of my 79 #3 carb with the correct O-Ring.

Hope that helps!

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Re: Accelerator pump rod travel

Post by EMS »

6Pipes wrote:I was having some trouble posting a pic with my narrative but shown above are a couple of shots of my 79 #3 carb with the correct O-Ring.

Hope that helps!

After you upload the picture to the Gallery, you open it again, scroll down below the picture where you see ImageBBCode and then copy the id from the window which in this case says [album 4401 album] and paste that into your post like this:

4401

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Re: Accelerator pump rod travel

Post by Kool_Biker »

Thanks chaps, this is really helpful.
With your pictures above, I have now positively identified the correct o-ring!
Many thanks for the excellent response.
Aris

P.S. Now I have some definite flow, back to getting the infamous pump rod to behave when opening the throttle. That is:
1. Travel long enough. Up to ~6mm according to Mike
2. Fast enough. This should be easily achieved with a stiffer spring, adding some washers to the existing set up, etc.

BTW here's a Utube link to the first ever start of my partially built CBX a few days ago ... good oil pressure though

Apologies if it is sounds Greek to you, that's what it is :D ...
Aris Hadjiaslanis
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Re: Accelerator pump rod travel

Post by 6Pipes »

Aris,

I enjoyed your video! What a great shop you have.

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Re: Accelerator pump rod travel

Post by NobleHops »

Aris! Awesome! Hope you don't mind, I edited your post to put your video in the 'youtube' tag to embed it directly.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

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Re: Accelerator pump rod travel

Post by Kool_Biker »

Success at last!

With the help of your pics I located the correct o-ring, reassembled the carbs, primed them and woo-hoo, the results as below.
P1050875 (2).jpg
And a pleasant side benefit, for those who have followed the entire blog, the accelerator rod travel has improved.
It now moves faster, more responsively from rest to it's stop.
The only explanation I can give is, the pump is no longer working against a blocked output? Maybe.

Thanks for all your support guys. We are getting there!
Aris
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Aris Hadjiaslanis
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Re: Accelerator pump rod travel

Post by Kool_Biker »

Almost 3 weeks after my last post above and lots of test runs of my now completed Z, I would like to thank the forum and in particular all you gurus for guiding but also challenging me with your recommendations to get my accelerator pump right.

Pick up on the throttle is now, to me at least, excellent and I look forward to many riding miles in the near future to prove under various road conditions.

If there is a lesson to be learned by us mere mortals is that with the forum resources, time, common sense and most important of all, perseverance you can really get things right in the end.
Cheers, Aris
Aris Hadjiaslanis
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Re: Accelerator pump rod travel

Post by NobleHops »

Kool_Biker wrote:Almost 3 weeks after my last post above and lots of test runs of my now completed Z...

Cheers, Aris
Ahem. Did you say "completed'?

Pics and a video or it didn't happen!

Very impressive Aris. Can't wait to see it.

N.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

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Re: Accelerator pump rod travel

Post by Kool_Biker »

Nils, kudos to you and all the good people supporting us!!!
P1060053 (2).jpg
Here's my Z, fully functional and ready for the road, less a couple of stickers and with my test exhaust as I haven't made my mind yet what to get in the end (opinions welcome!).
I will submit a video the day I get one, with pleasure.

Meanwhile may be some of you will be interested in a video of my GL 1000 K1, completed about a month ago, which by the way was the winning entry in a Randakk competition! Apologies if the place is inappropriate but the passion is the same, it's only the bike model that's different :)
http://www.youtube.com/watch?v=5NdViMxrGeU
Enjoy in hi resolution!

Best, Aris
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Aris Hadjiaslanis
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Re: Accelerator pump rod travel

Post by NobleHops »

Outstanding. That's what, 4 CBXs restored here in the last 12 months? Fantastic.

Great job Aris, it looks mint.

N.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

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