Author Topic: What's the worst that could happen?  (Read 4439 times)

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Offline Artf0rm

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Re: What's the worst that could happen?
« Reply #25 on: September 27, 2011, 08:10:42 pm »
I think my next step here is to static time the bike, at least that will eliminate that variable.  I have the instructions from the Dynatek S down stairs and I will pick up a timing light tomorrow.  I will update you guys in the evening.

Offline Retro Rocket

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Re: What's the worst that could happen?
« Reply #26 on: September 27, 2011, 09:01:35 pm »
Can i ask, why are you using CR's with a stock engine. I would install a stock set with the airbox for the run in period...

The reason i suggested this is because you don't really want to be screwing with carbs while you are running in that engine.
I am going to use fuel injection on my 1000cc build but will be doing the initial run in with carbs, then i'll tune in the injection set up..... ;)
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Offline Artf0rm

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Re: What's the worst that could happen?
« Reply #27 on: September 27, 2011, 09:29:58 pm »
Quote
The reason i suggested this is because you don't really want to be screwing with carbs while you are running in that engine.
I am going to use fuel injection on my 1000cc build but will be doing the initial run in with carbs, then i'll tune in the injection set up..... ;)

Understood.  Unfortunately I don't have access to a set of functional stock carbs and my custom oil tank is mounted where the airbox would sit. 

Offline Retro Rocket

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Re: What's the worst that could happen?
« Reply #28 on: September 27, 2011, 09:33:17 pm »
I'm actually thinking of running my bikes in on a dyno, faster, more consistant loads and if it breaks down i don't have to push it home.... ;D
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Offline phil71

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Re: What's the worst that could happen?
« Reply #29 on: September 27, 2011, 10:47:48 pm »
I dont know any other way to say this , so here goes.
You will NEVER get those CRs to run like a street bike. They're race carbs, they will never idle. EVER, because they don't have idle circuits. They're meant for high compression engines with huge cams and redlines in the 12,500 rpm range.
It's not simply that they don't belong on a street bike , they won't work. Chase your tail all fall if you want to.

Offline Artf0rm

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Re: What's the worst that could happen?
« Reply #30 on: September 27, 2011, 11:20:54 pm »
Phil71, my understanding is that this is absolutely true of the older versions of the CR's but the newer (which these are) versions are not impossible to get setup on "street" bikes.  With that said, until I can rule out some of the other variables I'm not giving up on them.  Especially since that would mean purchasing a set of sock carburetors to replace these or a rebuild of the snotty gross stock ones that I got with this bike. 

There are several folks on the board that have stated that they run CR-Specials on stock motors and there are advantages and disadvantages.   Right now I would just like to get to a point where turning over the bike doesn't involve guessing which end fire is going to come raining out of..

Offline phil71

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Re: What's the worst that could happen?
« Reply #31 on: September 28, 2011, 12:01:43 am »
After looking at keihin's entire current lineup of CR carbs, I can say for certain that, no matter what you do, you're staring down the barrel of a lot of compromises. Even if you did have a jet assortment handy, you'll still be occupied with keeping it running at every single stop sign and traffic light. It doesn't mean it wont be rideable, but it's never going to idle under 3k rpm. For all I know, you're building a race bike, but it really doesn't sound like it. I promise you, cleaning up those snotty old carbs is gonna take about 1/100th the time it will to get these race carbs doing anything but spitting fuel mist at you.

Offline phil71

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Re: What's the worst that could happen?
« Reply #32 on: September 28, 2011, 12:13:45 am »
also, don't buy a timing light. Your ignition setup is great, and the advance curve is taken care of. You're not going to need that timing light but you will need that $ for a host of other things.

Offline lucky

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Re: What's the worst that could happen?
« Reply #33 on: September 28, 2011, 01:46:14 am »
If this is a fresh build or the engine has been sitting around for awhile, I would recommend just turning the engine over and make sure you have oil pressure and oil is getting to the head. Easy to do and takes little time. Pull one of the exhaust tappet covers, flip the kill switch on and hit the starter button. You may have to cycle the starter a few times. Don't keep the starter spinning for to long. 10-15 sec should be good, 4 or 5 times. You should see oil pooling around the valve spring. If it is a high compression engine remove all the plugs that way the engine isn't fighting against itself and will allow the engine to spin freely. Good Luck I look forward to seeing how it all worked.


It may not show oil pressure just from turning the engine over with the starter.
It actually has to start and run for a few seconds.

Offline lucky

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Re: What's the worst that could happen?
« Reply #34 on: September 28, 2011, 01:53:49 am »
OK, here is the list of things I am considering:

1. Packing peanuts could be blocking on of the tubes? 
(I blew them out with compressed air but maybe I didn't get them all since some popped out of the back when I tried to start it)

2. Valve timing is somehow off? (I think I was pretty meticulous about the rebuild on the engine but everyone makes mistakes)

3. Compression is low on those 2 cylinders? (The engine has been sitting without being running for a few months after the rebuild.  Should I put a little oil in the cylinders through the spark plug holes?)

4. Carbs are F@#$ed somehow? (CR-Specials are completely clean but I understand they are temperamental by nature.  Perhaps I should take the whole bank ff and clean them them?) 

5. Ignition timing is off? (Not really sure how to time these things when they don't start?)

The other thing that I am considering is taking it to a guy that works on these bikes here locally and just letting him finish off the final details to make sure I didn't mess anything up.  Again, this whole thing makes me wonder what's the worst that I could do to it?  I did turn it over a number of times with the starter before installing all of the peripherals and compression tested it.  everything was around 110 (+/- 10%) so I'm not really sure how it would be compression issues.  I'm really at a loss.

You better get some help.
When you did the compression test on a engine that is not broken in, did you have the throttle wide open and all the other plugs out?

I' am outta here.

Offline wrenchmuch

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Re: What's the worst that could happen?
« Reply #35 on: September 28, 2011, 05:47:34 am »
The suggestion that #'s 2 and 4 have their plug wires swapped is a good one . Its always good to start with ignition before moving to fuel when trouble shooting . The fact that 1 and 3 ran might  point towards reasonably good timing of the dyna s . Did you happen to pull the plugs on the non running cylinders right after trying to start ? If so were they wet with fuel ? My understanding is that later Cr's have idle circuits early ones don't . Do you know what size the cr's are ? Anything larger than 29mm might be real hard to tune to a stock engine .
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Offline Artf0rm

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Re: What's the worst that could happen?
« Reply #36 on: September 28, 2011, 07:45:25 am »
Quote
You better get some help.

1. that's why I'm here. 2. I'm not ready to throw in the towel yet and hand it over.  This is my hobby and problem solving is fun.

Quote
The suggestion that #'s 2 and 4 have their plug wires swapped is a good one . Its always good to start with ignition before moving to fuel when trouble shooting . The fact that 1 and 3 ran might  point towards reasonably good timing of the dyna s . Did you happen to pull the plugs on the non running cylinders right after trying to start ? If so were they wet with fuel ? My understanding is that later Cr's have idle circuits early ones don't . Do you know what size the cr's are ? Anything larger than 29mm might be real hard to tune to a stock engine .

Thanks, I'll check that tonight.  The CR's are 29's.  I'm going to start with the timing per the instructions found here (http://www.austincaferacer.com/page/12/) and check the plugs are in the right place before I do anything else.  Then start looking at fuel.  More updated tonight. 

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Re: What's the worst that could happen?
« Reply #37 on: September 28, 2011, 08:02:30 am »
Well, from reading your posts so far, the worst is:  bent valves from timing chain improperly installed, scored cylinders from fuel wash and lack of oil, seized engine from oil pump not functioning, advancing flame front and consuming fire from carb issues, and lastly, you could shoot a flaming packing peanut out and ignite a pile of rags and burn the entire shop down.  That being said, you seem reckless, careless, and somewhat incompetent.  You have disregarded all suggestions that others have made.  I get that, we all have to start somewhere.  I would ask that you remain on the forum, listen carefully, and do what people here suggest.  At least until you have some experience under your belt, then you can go your own way with some sense of care for your machine. 

Offline phil71

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Re: What's the worst that could happen?
« Reply #38 on: September 28, 2011, 10:28:53 am »
Well, from reading your posts so far, the worst is:  bent valves from timing chain improperly installed, scored cylinders from fuel wash and lack of oil, seized engine from oil pump not functioning, advancing flame front and consuming fire from carb issues, and lastly, you could shoot a flaming packing peanut out and ignite a pile of rags and burn the entire shop down.  That being said, you seem reckless, careless, and somewhat incompetent.  You have disregarded all suggestions that others have made.  I get that, we all have to start somewhere.  I would ask that you remain on the forum, listen carefully, and do what people here suggest.  At least until you have some experience under your belt, then you can go your own way with some sense of care for your machine. 


Jesus H, King...... THAT'S tough love! I wouldn't have gone quite that far..
ArtfOrm, I sympathize with what you're going through, and just so you understand people's reaction to your problem, you've made some choices on the bike that are outside your experience level, and possibly violate various laws of physics, chemistry, fluidynamics, maybe even aerodynamics (Haven't seen your bodywork yet).
  I know you want someone to say "hey, that should all be totally do-able.. pour some mystery oil in the gas tank,stare at it for 20 mins  and it'll purr like a kitten".
   but there are far too many variables here, and the combined experience here still can't predict what it will take to make it run with all those changes.
   Saying you should get it closer to stock is not us trying to stunt your creativity, just trying to get some known data out of a ton of unknowns. You haven't even said what model CR you're running (probably3025s), but you have to try to appreciate what it says to all the old timers when you have $800 worth of carbs on an engine that can only run worse for the 'upgrade'....

Unless I miss my guess, you probably bought all that stuff from carpy's.. as he seems to be one of the only in-stock sources for 3035s, I'd call and tell them exactly what combination you're running, and ask for some baseline jet suggestions .

Offline Artf0rm

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Re: What's the worst that could happen?
« Reply #39 on: September 28, 2011, 12:10:19 pm »
Wow.  Regardless of technical knowledge that has to be the worst way to get anyone to listen to you.  I say that having previously picked through threads looking for post you have made King where I needed clarity on something.

I'm not trying to bolt on as much stuff to get this thing to go as fast as I possibly can.  I also really don't care about the CR carbs and it's not my intention to ignore any of the feedback here.  However, I would like to point out that since my last post regarding my plans tonight of working out the plugs and timing (both suggestions here) I haven't even made it back to the garage to touch the bike.  I'm all ears when it comes to suggestion and if it turns out I need rebuild services or a new set of carbs I would have most likely come here first to look for those services because I am pretty unsure of my ability to get these right the first time but I respect the community here.  With that said I'm not really sure how you got from A to C and where B (my disregard for everyone's input happened) but I'm also not that concerned (So I guess there's some disregard).   

I'm not sure about the reckless or careless but I will agree with the incompetent.  Competence comes from experience and research but practicum has to be in there somewhere.  I check this site almost everyday for something even if its just to see if I find something that I had no idea existed.  I spent hours reading pdf's of manuals for all of the internal engine work I did, when I was really out of depth I found someone local that could explain it all to me before I tried it and in a few cases I paid for the expertise of a few professionals that were nice enough to explain there work along the way.  Best I can say is that I'm trying to learn and be a part of the community around something I have interest in.  That and relate back the things that I have been told or figured out(hopefully not as gospel).     

Honestly, I got into this project for 2 reasons.  1) I thought it was a great way to work through some life changes, which is was 2) My dad had one when I was grown up.  Honestly, whether I go home tonight and it all works out or I light it on fire and roll it into a lake it's just not that fun checking this thread.  If I really wanted to I'm comfortable enough that I could burn it down and purchase a finished rebuild on CL tomorrow, or take this one to a pro and have it show up at my door shiny and perfect but that's really not what it's about is it?  I'll read on and may end up taking it to someone or replacing parts X,Y,Z but I appreciate the help along the way regardless as long as it's constructive.

Offline WarwickE36

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Re: What's the worst that could happen?
« Reply #40 on: September 28, 2011, 12:29:31 pm »
Quote
5) Simply put... No.  Does the Dynatek S require that?

6) Again, Simply put.  Yes.  The only modifications I have made are the Dyna coils, the Dyna S kit, Carpy's Yoshi knockoff 4-1 exhaust.

5. Dyna S is statically timed with a test light, no need for timing light.  It is set at full advance, with the rotor manually twisted (for 1/4 and 2/3).  Dynatek's website has manually available for each model if you don't have yours.  Its easy if you understand the terminology.  And have a test light.

6.  Did you make sure to wire up the coils correctly?  Its possible one coil isn't firing at all.  I could see if you wired the trigger backwards from the Dyna S it may only fire 1 coil.  Double, triple, quadruple check the wiring.

TIPPull all plugs, install each plug in its respective plug wire.  Take some regular insulated wire and cut 4 2 foot sections...strip the wires at each end about 2" on each end.  Wrap each spark plug threaded section with the exposed wire, and attach the other end to ground (battery on bare frame...you can use a pair of vice grips to clamp it so you dont have to hold it)  NOW, make sure ignition is ON and kill switch is ON.  Rotate the motor by hand, either using the wheel method or a wrench on the big nut on the advancer.  Slowly rotate the motor and watch the plugs fire when they hit their respective marks.  1/4 should fire at the same time, 2/3 should do the same.  You can check timing this way as well if you have a clue about how ignition timing works. 
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Offline Artf0rm

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Re: What's the worst that could happen?
« Reply #41 on: September 29, 2011, 06:18:30 pm »
Just fyi.. It starts and idles.  I had the plugs wires crossed 2 and 4 and I obviously needed to static time it.   Thanks for the help all.  Especially, phil7.  King, you're a flaming packing peanut and you can blow it out of my tailpipe.   

Offline Tugboat

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Re: What's the worst that could happen?
« Reply #42 on: September 30, 2011, 07:51:57 am »
And....... scene :)
If it's worth doing, it's worth doing twice.

Offline phil71

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Re: What's the worst that could happen?
« Reply #43 on: September 30, 2011, 08:06:23 am »
nice! now tune tune tune. This may involve riding fast,  down some back roads. I hope you're okay with that.

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Re: What's the worst that could happen?
« Reply #44 on: September 30, 2011, 08:12:05 am »
Crossed 2-4?  How does that even happen? Anyway, glad it is running.  BTW, I much prefer respect over love.

Offline Duanob

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Re: What's the worst that could happen?
« Reply #45 on: September 30, 2011, 09:37:40 am »
King you're on fire in this thread. I guess we all forget where we came from when we first got our bikes and had no clue. We all learn eventually.

Dyna-S ignition: Sure you don't need a timing light but any self respecting mechanic will have one somewhere in his collection of tools and frankly I prefer to time my Dyna-S with one. I can see exactly where it idles as well as where the advance is and set the timing exactly where it needs to be when it's running.
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