Kawasaki Concours Forum

The C10, aka Kawasaki Concours - The Original => The Bike - C10 => Topic started by: m in sc on January 25, 2021, 03:14:11 PM

Title: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 25, 2021, 03:14:11 PM
So,

both of my c10s are cold blooded on throttle response even after idling for quite  abit warming up prior to a ride.. Both have carbs gone through completely and correctly, and the bikes are dead stock and have no issues otherwise.  But they are both fairly cold blooded to take throttle nicely until a few minutes after riding, even on warmer days. after that, they are perfect and responsive  all day long.

Friend of mine with a 2000 has same issue. Its livable but annoying.

 I've produred new carb slide diaphragms in an effort to cure this (figure the old ones are just that : old and not responding as well cold). they aren't torn and are installed correclty. anybody else tried replacing them this and succeeded in making the carbs better in colder engine situations?
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: kkja13 on January 25, 2021, 04:12:55 PM
Mine is also bone stock.  It is warm enough to take throttle by the time I get my helmet, jacket and gloves on.  I haven't done any carb work to mine. 
Have you tried adjusting the mixture screws?
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: George R. Young on January 25, 2021, 04:55:58 PM
I noticed my 2001 was kind of cold blooded, particularly after moving from 125 main jets to 120s. I shimmed the needles with #4 washers, 1/8" ID, 1/4" OD, 0.032" thick. Problem went away.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: DC Concours on January 25, 2021, 06:04:55 PM
Cold blooded. Mine takes a 3-5 min idling warmup and a ride around the block to accept crisp throttle responses. I think this is just how they are.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: cra-z1000 on January 25, 2021, 06:32:18 PM
Mine was pretty cold blooded before The last time I went through the carbs . Not sure what I did different but she warms up quick now and has great throttle response shortly after starting . I did use some Outlaw Racing brand carb kits last time (which seem to be nice quality and very complete )

https://www.amazon.com/dp/B00NHVT0CS/ref=cm_sw_r_cp_apa_fabc_Ma5dGb92RHSWR
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 26, 2021, 05:19:07 AM
i have the fuel screws dialed in correctly, i tried that early on.  i did replace the diaphragms last night, it def seemed to help. were no flaws with the old ones but they were def stiffer than the new ones.  was easy, took less than an hour. when the weather dries out i'll take it out for a ride see if its better to warm up. i may shim the needles a bit
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 27, 2021, 12:57:30 PM
just as fyi. diaphragms replaced. if you look at the originals, they were starting to mis-shape a bit on the 'cone'

(http://www.2strokeworld.net/wp-content/uploads/99-concours/diaphragm_1.jpg)

(http://www.2strokeworld.net/wp-content/uploads/99-concours/diaphragm_2.jpg)

(http://www.2strokeworld.net/wp-content/uploads/99-concours/diaphragm_3.jpg)
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: gpineau on January 27, 2021, 03:35:52 PM
Loving my fuel injected Connie.
Today at 22 degrees and half a foot of snow on the ground.  I went outside and pulled the blankets off  my connie and my Vstar.  Powered on, hit the starter and both started and went to idle.  I waited 5-15 minutes , shut them off, put them back to bed. Will do it again next week.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: DC Concours on January 27, 2021, 03:59:20 PM
Why do you do that? I don't think it is good for your bike.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 27, 2021, 05:15:32 PM
I have fuel injected bikes as well..  whats your point?

Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: gpineau on January 27, 2021, 06:54:48 PM
Why do you do that? I don't think it is good for your bike.

I see opinions go both ways. I  think it is a good thing. Letting it run will keep all the engine components and gaskets lubricated, eliminates condensation buildup, ensures fuel lines will not gum up, and recharges the battery. I let it run long enough that the condensation in the pipes is gone and it is running smooth.
I don t think it is good to start it unless your going to let it get up to temperature to drive out any condensation and let the hot oil get distributed throughout the engine.

Why do you think it is not good for a bike ?
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 27, 2021, 07:52:53 PM
its not good. needs to get to full temp. you are creating condensation in the motor doing that, and its not burning off. this is corrosive for internal engine components. if you are going to run, it let it run for about 20 minutes.  also the oil never gets fully warmed up in 5 minutes. let the fan at least cycle once. .02

as far as cold starting, i can get my carburated 45 year old 2 strokes to come right to an idle and run just fine in cold weather. then again, they don't rely on rubber diaphragms to lift.  If you know how to tune and repair and maintain a carb, not an issue.  I was just asking how common an issue it was amongst the c10 owners.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: DC Concours on January 27, 2021, 11:10:25 PM
I think you should ride it for 20-30 minutes to completely rid the water that forms in the engine/trans and stop it from causing sludge. Just know this from smaller lawn care machines engines I have neglected or run periodically and ended up having to tear down and clean.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: Boomer on January 28, 2021, 02:26:14 AM
I start my bikes periodically if I'm not riding them but I always let them run until the fan(s) kick in and switch off again.
On the C10 I will sometimes need to blip the throttle or part-enrich it to bring the idle up to 2000rpm if it's cold (below freezing) or the fan never kicks in.

I don't think the C10 is any different to other carb bikes w.r.t. cold bloodedness. I think we are all getting used to modern fuel-injected/engine-managed "digital" bikes and are forgetting that the C10 is pure analogue. My GS550E was the same, as was the CB750F2,... and the XS500 was a complete dog to ride if you didn't let her warm up fully, but they did suffer from over-cooling issues in cold weather.

Mark, where didja get those diaphragms from? Mine are usable but are pretty stiff and could probably do with replacement.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 28, 2021, 08:56:31 AM
Quote
Mark, where didja get those diaphragms from? Mine are usable but are pretty stiff and could probably do with replacement.

just picked them up off ebay. was like 20 for all 4. we'll see how they hold up, the material feels good, so we'll see. I saved the old ones just in case.

I looked at how many were prior sold and the feedback. looked ok so took a chance. have a second set on the way for the red 2000.



 
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: Stasch on January 28, 2021, 09:52:49 AM
Please report back on how it helped with your original concerns.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: DC Concours on January 28, 2021, 12:05:26 PM
Wow. that is a great deal. Yes, please let us know how they work out for you. and perhaps post a link to the seller so we can buy if we need some.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on January 28, 2021, 12:17:30 PM
they may eventually turn out to be garbage but so far so good. I'll def take the 99 out this weekend. Like said, just cold starting int he garage, it def takes partial throttle easier earlier than before after warming up for a few  mins. 1-2 minute on choke, then 3-5 idling, then trying partial throttle. 45 ish degrees ambient air temp. 

 4PCS For KAWASAKI ZG1000 ZG 1000 1986-2006 Carburetor Vacuum Membrane Diaphragm https://ebay.us/KF6QRn
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on February 06, 2021, 03:16:47 PM
so took bike out today. def better for sure. then shimmed needles, even better.  def worth the work, easy.

low end def helped by the needle shims.  just fyi. was in mid 40's today.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: kkja13 on February 08, 2021, 11:03:14 AM
How thick are the shims?
What changed by adding the shims?
Curious...
Thanks!
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on February 08, 2021, 11:33:22 AM
the 4 i measured were .038". ordered a bag of #10 washers from macmaster and measured with calipers, dug up 4 pretty quick that were exact.

it just richens the fuel when its on the needle circuit. more 'meat' in the throttle response down low and in the mid-range, def winds up quicker. I did the diaphragms 1st, was better, but the shims gave it a bit 'more' there and def better mid-range. had my friend David ride behind me on his new Z900 and said it didn't 'smell' any richer at all that he could tell, and hes super sensitive to it. did a bunch of mid-range runs and really good.  will repeat this on the red 2000.   they both ran good, but this is a def improvement.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: connie_rider on February 08, 2021, 03:02:13 PM
Thanx m in SC, I just bought a set.
 4PCS For KAWASAKI ZG1000 ZG 1000 1986-2006 Carburetor Vacuum Membrane Diaphragm https://ebay.us/KF6QRn
I have a set of ZX-1000 carbs with questionable diaphragm's.

Ride safe, Ted
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on February 09, 2021, 08:53:41 AM
as a second follow up... rode the c10 into work via the interstate this morning, the 4000-6 rpm roll-ons in traffic to pass at half throttle to 3/4 are def better as well. 



 
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on February 21, 2021, 04:56:13 PM
did the naked 2000 c10 last night, rode it a bit today, same treatment. new diaphragms and shimmed needles (did it all at same time this time). way better. 
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: Boomer on February 22, 2021, 04:33:00 AM
Thanks Mark  ;D
I bought a brand new set of carbs for a knockdown price. They are all nice and shiny.  ;D 8)  :banana
If they give better responsiveness in the nekkid C10 I'm building, then I may well replace the ancient diaphragms in my 32 year old carbs on Otto as well.
Title: Re: COLD BLOODED c10. (carb diaphragms?)
Post by: m in sc on February 22, 2021, 08:40:24 AM
Boomer,. i saw that, that's an awesome score.   8)