CB500 Four Dutch Dyke Racer ( CARB QUESTIONS )
- Thread starter Tetter
- Start date
Re: CB500 Four Dutch Dyke Racer
Spend some time in the shed today, not to work on the bike though....
Made myself a nice new workbench with parts from my parents old kitchen, and cleaned the whole place.
Needed to have the bike out, to make a nice carpet for her, and did a photoshoot in front of the door to Mordor !?(.... everytime I go through, I'm gone for a long time and get back all black and smelly.
)
And a view of the new cockpit, with the oilpressure led in the Top triple nut.
Spend some time in the shed today, not to work on the bike though....
Made myself a nice new workbench with parts from my parents old kitchen, and cleaned the whole place.
Needed to have the bike out, to make a nice carpet for her, and did a photoshoot in front of the door to Mordor !?(.... everytime I go through, I'm gone for a long time and get back all black and smelly.
)
And a view of the new cockpit, with the oilpressure led in the Top triple nut.
ShiZhiLong
我爱我自己!
Re: CB500 Four Dutch Dyke Racer
太牛了!
太牛了!
Re: CB500 Four Dutch Dyke Racer
Today I made the first drive of the season.
The speedo seems to think I'm running 200 KM ( approx 124 M/ph ) in 3rd gear ! :
I think the ignition cable is to clase to the speedo sensor cable. I will re-route it and try again
Today I made the first drive of the season.
The speedo seems to think I'm running 200 KM ( approx 124 M/ph ) in 3rd gear ! :
I think the ignition cable is to clase to the speedo sensor cable. I will re-route it and try again
Re: CB500 Four Dutch Dyke Racer
I went to a swap meet today.
Needed nothing, just a "normal size" tacho cable, and actually that's all I bought :-\
Was a nice ride though, I really need to start tuning.
I think the needles need to be in the top position ( clips in low pos ), as she runs better if I leave the choke on a bit.
In 3 weeks I will have a week of, and I want to check the ignition with a stroboscoop and check the balance of the carbs.
Oh and I rereouted the speedo cable, but still about double the speed I'm really riding.
I have now changed the measurements in the cyclo computer by half that should do the trick.
I checked it on a speed indicator pole 104 was really 50 and 145 really 70.
We'll see the next ride if it worked out.
There were some nice bike's, also on the parking.
A nice BMW Sidecar Café
A German Cb500 four café bobber ( I live close to the border )
Same builder, also a Honda, with a nice single side mounted rearwheel
I went to a swap meet today.
Needed nothing, just a "normal size" tacho cable, and actually that's all I bought :-\
Was a nice ride though, I really need to start tuning.
I think the needles need to be in the top position ( clips in low pos ), as she runs better if I leave the choke on a bit.
In 3 weeks I will have a week of, and I want to check the ignition with a stroboscoop and check the balance of the carbs.
Oh and I rereouted the speedo cable, but still about double the speed I'm really riding.
I have now changed the measurements in the cyclo computer by half that should do the trick.
I checked it on a speed indicator pole 104 was really 50 and 145 really 70.
We'll see the next ride if it worked out.
There were some nice bike's, also on the parking.
A nice BMW Sidecar Café
A German Cb500 four café bobber ( I live close to the border )
Same builder, also a Honda, with a nice single side mounted rearwheel
Re: CB500 Four Dutch Dyke Racer
As the dyke racer is now about finished, I will have her tuned ( carbs etc ) in 2 weeks time, and after that a photoshoot at the "skydive" airport. I'll post the pictures.
I have bought a new project.
http://www.dotheton.com/forum/index.php?topic=35861.0
The Dyke Racer :
As the dyke racer is now about finished, I will have her tuned ( carbs etc ) in 2 weeks time, and after that a photoshoot at the "skydive" airport. I'll post the pictures.
I have bought a new project.
http://www.dotheton.com/forum/index.php?topic=35861.0
The Dyke Racer :
Re: CB500 Four Dutch Dyke Racer ( ALMOST CRASHED )
Planned a ride yesterday to mt parents for a BBQ.
Started the old gal after 4 months :-[ ( sorry need to get out more )
After about 10 miles the rearwheel suddenly blocked full !
In a reflex grap the clutch, but that didn't work. Left a 12 meters black skidmark ! But kept the machine up straight.
The batterie box is broken, and the batterie fell down, on the reartire, and was carried by it till it hit the rearfork.
This is what is left of the batterie.
And this is where it hit the fork.
The plastic inner fender was also torn up :-X
BBQ was fine, and I have a new story to tell 8)
This is what riding the old ladies is about though, and what makes it that more exiting and fun when you do make a complete trip......
Planned a ride yesterday to mt parents for a BBQ.
Started the old gal after 4 months :-[ ( sorry need to get out more )
After about 10 miles the rearwheel suddenly blocked full !
In a reflex grap the clutch, but that didn't work. Left a 12 meters black skidmark ! But kept the machine up straight.
The batterie box is broken, and the batterie fell down, on the reartire, and was carried by it till it hit the rearfork.
This is what is left of the batterie.
And this is where it hit the fork.
The plastic inner fender was also torn up :-X
BBQ was fine, and I have a new story to tell 8)
This is what riding the old ladies is about though, and what makes it that more exiting and fun when you do make a complete trip......
DuckHunterJon
Active Member
Re: CB500 Four Dutch Dyke Racer ( ALMOST CRASHED )
Ouch, glad you kept it upright - could have been much worse!
Sent from my DROID RAZR using Tapatalk 2
Ouch, glad you kept it upright - could have been much worse!
Sent from my DROID RAZR using Tapatalk 2
Hi Gents, as posted in 1-800-cafe help as well:
http://www.dotheton.com/forum/index.php?topic=44865.new#new
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Dear all,
Can somebody explain to me where I will notice what adjustments in the carbs.
For example:
Putting the needle Higher, will this result in a better start? or a good "pick up"? or gasresponce? or higher refs ?
My CB500 is at this time not correct adjusted, that I know for sure, but I don't want to go messing around with the wrong parameters.
Currently the CB has a very bad cold start ( needs almost always brake cleaner or starterpilot )and while riding it runs best with the choke "on" a bit.
Though when I pull the throttle full open, the choke ( automatically I guess ) is in "open" stage again, and it runs bad ( lean ? )
NOTE: I have to mention I run open velocity stacks.
I have now recently rebuild the carbs, as they were leaking heavily All needles, jets and rings have been replaced, and the carbs have had an ultrasonic bath.
She already runs a lot better then before the re-build, but I feel they are not there yet.
The needles I have put in the Mid position of the 5 grooves ( I think this is the standard ? ) and I have put the mixture screws 1 3/4 out, as in the Manual.
I feel I should change something still.
Where to start ?
Putting the needles in a higher ( highest ? ) position ?
Or shoul I have the mixture screws less open due to the stacks ?
After that synch the vacuum ?
Does any of the above changes also affect the bad cold start ?
Or could this be ignition timing ?
I have changed the ignition with an electronic one when I re-build the carbs as well, put the timing on "static" will adjusting/ checking this while running change a lot ?
Please can anybody answer ( some of ) my questions ?
http://www.dotheton.com/forum/index.php?topic=44865.new#new
-------------------------------------------------------------------------------------------------------------
Dear all,
Can somebody explain to me where I will notice what adjustments in the carbs.
For example:
Putting the needle Higher, will this result in a better start? or a good "pick up"? or gasresponce? or higher refs ?
My CB500 is at this time not correct adjusted, that I know for sure, but I don't want to go messing around with the wrong parameters.
Currently the CB has a very bad cold start ( needs almost always brake cleaner or starterpilot )and while riding it runs best with the choke "on" a bit.
Though when I pull the throttle full open, the choke ( automatically I guess ) is in "open" stage again, and it runs bad ( lean ? )
NOTE: I have to mention I run open velocity stacks.
I have now recently rebuild the carbs, as they were leaking heavily All needles, jets and rings have been replaced, and the carbs have had an ultrasonic bath.
She already runs a lot better then before the re-build, but I feel they are not there yet.
The needles I have put in the Mid position of the 5 grooves ( I think this is the standard ? ) and I have put the mixture screws 1 3/4 out, as in the Manual.
I feel I should change something still.
Where to start ?
Putting the needles in a higher ( highest ? ) position ?
Or shoul I have the mixture screws less open due to the stacks ?
After that synch the vacuum ?
Does any of the above changes also affect the bad cold start ?
Or could this be ignition timing ?
I have changed the ignition with an electronic one when I re-build the carbs as well, put the timing on "static" will adjusting/ checking this while running change a lot ?
Please can anybody answer ( some of ) my questions ?
MotorbikeBruno
Over 1,000 Posts
Well, first off, you have a great looking bike!
If you are running open velocity stacks, you are getting far more air than stock, so the stock pilot jet will be too lean. You said you have the mixture screws set to stock, so I would Richen the circuit by 1 turn initially to see how that goes. Many times you'll want to go up one size on the pilot to account for more air coming in at idle, this should help with the starting of the bike too. This diagram has been in many threads and helps quite a bit for telling you what things work at each throttle position on a carburetor.
http://www.dansmc.com/carb_jet_usage1.jpg
I would get the bike to idle well first, then sync, since you really want to synchronize the bike at idle. I would also verify ignition timing as you also stated, have the cover off and use a timing gun to verify that you are correct on timing will be of great help. Also make sure the advancer mechanism is doing it's job
I'm currently working on a 71' cb500, and hope to finish putting the engine back together in the coming weeks, I'll be in the same spot you are in now, so let me know how yours goes! 8)
If you are running open velocity stacks, you are getting far more air than stock, so the stock pilot jet will be too lean. You said you have the mixture screws set to stock, so I would Richen the circuit by 1 turn initially to see how that goes. Many times you'll want to go up one size on the pilot to account for more air coming in at idle, this should help with the starting of the bike too. This diagram has been in many threads and helps quite a bit for telling you what things work at each throttle position on a carburetor.
http://www.dansmc.com/carb_jet_usage1.jpg
I would get the bike to idle well first, then sync, since you really want to synchronize the bike at idle. I would also verify ignition timing as you also stated, have the cover off and use a timing gun to verify that you are correct on timing will be of great help. Also make sure the advancer mechanism is doing it's job
I'm currently working on a 71' cb500, and hope to finish putting the engine back together in the coming weeks, I'll be in the same spot you are in now, so let me know how yours goes! 8)
MotorbikeBruno
Over 1,000 Posts
I'll go take a look. I came across this info on SOHC forums..
The extra tricky bit with the 550 and earlier carbs in other models, is that they have no enrichment pump to compensate for the rapid loss of vacuum when the slides are opened quickly. Therefore, these carbs are adjusted sufficiently rich to achieve adequate throttle response with moderate changes in throttle position.
So maybe going from 78 to 100 was actually a bad idea! I was always wondering why (on my 76 cb550) it never needed a larger pilot jet...
Looks like if you turn the air screw IN it makes it run more RICH. So I would try turning your screw OUT 1 turn each and see how she reacts. How do the spark plugs look again?
The extra tricky bit with the 550 and earlier carbs in other models, is that they have no enrichment pump to compensate for the rapid loss of vacuum when the slides are opened quickly. Therefore, these carbs are adjusted sufficiently rich to achieve adequate throttle response with moderate changes in throttle position.
So maybe going from 78 to 100 was actually a bad idea! I was always wondering why (on my 76 cb550) it never needed a larger pilot jet...
Looks like if you turn the air screw IN it makes it run more RICH. So I would try turning your screw OUT 1 turn each and see how she reacts. How do the spark plugs look again?
MotorbikeBruno
Over 1,000 Posts
Tetter, any updates? Did you try leaning it out to get it to start more easily?
No, sorry no updates yet.
It's been far too cold here in the Netherlands to work on carbs.
Getting warmer now, hope to find some time fir it soon.
In the meantime i'm also building a CB750 K6.
That, a full time job and 2 kids..........
Looking forward to summertime, longer days, better temp for both building and riding!
It's been far too cold here in the Netherlands to work on carbs.
Getting warmer now, hope to find some time fir it soon.
In the meantime i'm also building a CB750 K6.
That, a full time job and 2 kids..........
Looking forward to summertime, longer days, better temp for both building and riding!
