Seeley 519 CB750
- Thread starter surffly
- Start date
the bigger the better is the rule for ride-giditty, the actual structure is the diameter of the inner bearing races and bearing spacers clamped as one by axl nut torque force,that is why it is better in your case not to go with 15mm bore bearings the actual "tube" diameter clamped structure would be reduced further
the major draw back of the 15 axle is the available clamping force as the thread strength/diameter is the limit of that force
it probably will be fine but i wouldnt doubt that the axle could be bent if a feller hits that OOOHHH SHIIIT ! pothoal at speed
the major draw back of the 15 axle is the available clamping force as the thread strength/diameter is the limit of that force
it probably will be fine but i wouldnt doubt that the axle could be bent if a feller hits that OOOHHH SHIIIT ! pothoal at speed
Nicely explained XB. This is one of the most important elements of the chassis design, and incredibly overlooked and/or underestimated by the majority of people. Precisely fitting proper parts are critical in achieving the available structural stiffness, and it doesn't take much to severely reduce it. If the clamped together assembly of arm components, spacers and inner races is compromised an any way, the loads then will fall on the axle itself in which case the small diameter becomes much more of an issue. The small axle no doubt can achieve sufficient clamping pressure, but I'd bet it is not far away from stripping the threads to do so. Far better to have the axle large enough that you have no concern over the tightening torque so you can simply crank it down hard without a torque wrench and no worries.
surffly
Over 1,000 Posts
Had a free night so started working on rebuilding the OEM carbs for the bike. While I remain unsure exactly what carbs I will run on this bike I figure it is easiest to get up and running with the stock carbs before thinking about running smoothbores or sidedrafts. Idea is that I always talk to people embarking on a project to keep it as stock as possible to develop a base line. This also falls into the category of “can get done at home during the week” so no reason not to.
The person I bought the parts bike from included a clean set of carbs. So far everything looks great and they will work well. I assume they were drained and stored correctly for many years. The rubber bits are dry, but nothing seems rotten or damaged. Huge plus.
You can see in the pictures that they are fairly clean both inside and out.
When working on the kitchen table it is best to use a pizza box to keep the stale junk off the wood.
Like I said, I assume that these were removed from a running bike, drained and then placed on a shelf. Cant ask for much more then that. Good carburetors are becoming harder to find. Im sure right now Geeto is ready to get in his car and drive over here to punch me…..
Plan is to strip them down, clean them, inspect and then rebuild. I only ever use OEM Honda parts in my fuel systems. Sure the K&L kits are cheaper, but I have found that they fit poorly, include the wrong parts and do no hold up to modern ethanol fuel well.
Will be using some pinsol and water to clean them up. Normally I do my own soda blasting on carbs, but these do not really need it. And since I am not cleaning up the rest of the bike I don’t think I need a full show job on the outside of the carbs.
With the bowls off and the floats out I removed the needle/seats. I keep them together as they are a “matched” set. Have mixed them up, or seen others not keep track of it and chase leaks down the line.
They look serviceable. Replacements are expensive.
I have to check my other parts and research a bit, but my first instinct is that the upper two holes (ones to the right in the picture) have been enlarged. I remember reading about people doing this. Think HondaMan had some posts about it.
Main is 105
Jet 40
Will have to look up what stock is, I know these are in the correct range though. Will need to buy a few sets of brass anyway to tune.
This one always gets me. Before I start looking though old Micro Phish from Honda, can someone tell me if this is stock?
I want to say that every freaking rack I have has at least one “odd” bolt out. This time one is a screw and the other three are bolts, other times visa versa. Just something funny I noticed.
My mind wondered and I went into full tare down mode.
I have done so many racks by taking them fully apart it is just a force of habit. DO NOT loose those little spacers if you do happen to take the arms off. Right after I took them off, I put them back on. Zero need to go that deep on these.
Once the backing plate is off (8 screws) the choke arms can be removed.
The main fuel inlet cross over is something I think some people forget about.
I don’t think the aftermarket kits come with the O-rings for this.
675B castings. Will need to double check exactly what these were off of.
Don’t leave the spring inside.
The large ring on the top of the bodies holds keeps the piston slides in place.
Can see some “junk” on the chrome, its not deep scoring.
Will need to dig a little deeper to make sure the needles are set to the proper depth
And to keep with the food theme a Chinese food container is used to keep al the hardware safe.
Will stop on my way home for some PinSol and get these parts soaking and cleaned up. After they are fully rebuilt I will put them aside until I am ready to start the bike for the first time.
This project, and many others is more of a sum of small projects.
I have been trying to focus on each task and cross things off the list as I can get to them. If my garage was attached to where I live and I could wrench more regularly then maybe it would be better to have a flow, but since I don’t I work on what I can, when I can.
The person I bought the parts bike from included a clean set of carbs. So far everything looks great and they will work well. I assume they were drained and stored correctly for many years. The rubber bits are dry, but nothing seems rotten or damaged. Huge plus.
You can see in the pictures that they are fairly clean both inside and out.
When working on the kitchen table it is best to use a pizza box to keep the stale junk off the wood.
Like I said, I assume that these were removed from a running bike, drained and then placed on a shelf. Cant ask for much more then that. Good carburetors are becoming harder to find. Im sure right now Geeto is ready to get in his car and drive over here to punch me…..
Plan is to strip them down, clean them, inspect and then rebuild. I only ever use OEM Honda parts in my fuel systems. Sure the K&L kits are cheaper, but I have found that they fit poorly, include the wrong parts and do no hold up to modern ethanol fuel well.
Will be using some pinsol and water to clean them up. Normally I do my own soda blasting on carbs, but these do not really need it. And since I am not cleaning up the rest of the bike I don’t think I need a full show job on the outside of the carbs.
With the bowls off and the floats out I removed the needle/seats. I keep them together as they are a “matched” set. Have mixed them up, or seen others not keep track of it and chase leaks down the line.
They look serviceable. Replacements are expensive.
I have to check my other parts and research a bit, but my first instinct is that the upper two holes (ones to the right in the picture) have been enlarged. I remember reading about people doing this. Think HondaMan had some posts about it.
Main is 105
Jet 40
Will have to look up what stock is, I know these are in the correct range though. Will need to buy a few sets of brass anyway to tune.
This one always gets me. Before I start looking though old Micro Phish from Honda, can someone tell me if this is stock?
I want to say that every freaking rack I have has at least one “odd” bolt out. This time one is a screw and the other three are bolts, other times visa versa. Just something funny I noticed.
My mind wondered and I went into full tare down mode.
I have done so many racks by taking them fully apart it is just a force of habit. DO NOT loose those little spacers if you do happen to take the arms off. Right after I took them off, I put them back on. Zero need to go that deep on these.
Once the backing plate is off (8 screws) the choke arms can be removed.
The main fuel inlet cross over is something I think some people forget about.
I don’t think the aftermarket kits come with the O-rings for this.
675B castings. Will need to double check exactly what these were off of.
Don’t leave the spring inside.
The large ring on the top of the bodies holds keeps the piston slides in place.
Can see some “junk” on the chrome, its not deep scoring.
Will need to dig a little deeper to make sure the needles are set to the proper depth
And to keep with the food theme a Chinese food container is used to keep al the hardware safe.
Will stop on my way home for some PinSol and get these parts soaking and cleaned up. After they are fully rebuilt I will put them aside until I am ready to start the bike for the first time.
This project, and many others is more of a sum of small projects.
I have been trying to focus on each task and cross things off the list as I can get to them. If my garage was attached to where I live and I could wrench more regularly then maybe it would be better to have a flow, but since I don’t I work on what I can, when I can.
they are better than VM mikunis mainly because of the oval section in the middlenot a bad idea to have a close look at the choke gea-teens for cracks/starting to come apart..and the lifter arm gets sloppy where it lifts the deal and can come undone while running down the rode leaving you with a mysterious ishoe happened to me with the SL350 carbs which are just a scaled down 750KO style carb
surffly
Over 1,000 Posts
Took some time while I should have been working and messed around with CAD. While nothing ground breaking for many, it was a set in being able to show the parts that I either need to make, or have someone make for me. In school I had used CREO a bit so picking up SolidWorks was not that bad. Looking forward to using it more both at work, and with my motorcycle hobby. Figure the only way to get better is to use it more. One of the draftsmen at the office was able to help show me better ways to draw the part so that changes can be made down the line. Neat stuff. Slowly chipping away at the in-house machinist to see his sense of humor for “extra circular activities” in the shop. He is a young guy and a hot rodder so I am hopeful he will be amenable to showing me a few things.
First is the end cap for the swingarm. The smaller OD step will fit inside of the swingarm tubing. I have seen some of the original ones flex, so I made this one fairly beefy. Each of the steps is 6mm “deep”. This seems like a rather simple piece to make.
The other part is the internal axle adjustor. After reading more about swingarm design I have learned that the idea should be to have this fit as tight as reasonable to the inside of the swingarm so that when everything is tightened up it locks together. The hole on the end will be tapped to use the OEM Honda bolts. Will need to figure out what the thread is on them. I assume 1.25
I need to make a few more measurements before I am done. Will have to work out the best location for the axle hole so that it allows for the full range or adjustment.
Again, no delusions that these are the most complicated things to draw, or make….but its part of the process.
Just leaves the front motor mount to make. Plan to use the high tech “pizza box” method. Will need to break out my most precise sharpie marker and sharpest blade on the jigsaw.
First is the end cap for the swingarm. The smaller OD step will fit inside of the swingarm tubing. I have seen some of the original ones flex, so I made this one fairly beefy. Each of the steps is 6mm “deep”. This seems like a rather simple piece to make.
The other part is the internal axle adjustor. After reading more about swingarm design I have learned that the idea should be to have this fit as tight as reasonable to the inside of the swingarm so that when everything is tightened up it locks together. The hole on the end will be tapped to use the OEM Honda bolts. Will need to figure out what the thread is on them. I assume 1.25
I need to make a few more measurements before I am done. Will have to work out the best location for the axle hole so that it allows for the full range or adjustment.
Again, no delusions that these are the most complicated things to draw, or make….but its part of the process.
Just leaves the front motor mount to make. Plan to use the high tech “pizza box” method. Will need to break out my most precise sharpie marker and sharpest blade on the jigsaw.
surffly
Over 1,000 Posts
Snuck away for some garage time last night.
I tried to mess with the hub that supposed to have been on the Seeley at some point. I think that it is a CB550 hub, but not 100% sure.
Idea was to take the axle reducer, brake drum and sprocket carrier off of the hub and place them on the CB750 wheel that I have in the frame now. If you remember I found that all of the CB750 parts did not fit as they were to wide for the swingarm. Also the sprocket carrier pushed the wheel assembly off center to the right.
Well I couldn’t get the retaining ring off of the hub to remove the sprocket carrier. What a pain. Yes I know it is reversed thread, but is taking one hell of a pounding to remove. Not sure what Honda was trying to do by using these parts. And even at that point I don’t see how all this jazz will work with the CB750 wheels.
So after fighting the hub for a while I decided to just mount the hub in the frame. And low and behold…..more issues. Now the unit is slightly to narrow! Maybe I am not looking at it right. I didn’t tighten everything down, it just seemed like more space to take up then normal.
Here is the picture of the original parts that I had to work with. You can see the gap.
And another one of the spacers I had around.
The OEM CB750 one. After thinking about things and looking at the pictures again, I might have things out of order?
The one on the axle in the above picture normally goes into the sprocket carrier side right?
Will have to take another look.
Honestly buy the end of the night it was getting late and I was rather frustrated as this bike seemed to be fighting me at every turn.
I tried to mess with the hub that supposed to have been on the Seeley at some point. I think that it is a CB550 hub, but not 100% sure.
Idea was to take the axle reducer, brake drum and sprocket carrier off of the hub and place them on the CB750 wheel that I have in the frame now. If you remember I found that all of the CB750 parts did not fit as they were to wide for the swingarm. Also the sprocket carrier pushed the wheel assembly off center to the right.
Well I couldn’t get the retaining ring off of the hub to remove the sprocket carrier. What a pain. Yes I know it is reversed thread, but is taking one hell of a pounding to remove. Not sure what Honda was trying to do by using these parts. And even at that point I don’t see how all this jazz will work with the CB750 wheels.
So after fighting the hub for a while I decided to just mount the hub in the frame. And low and behold…..more issues. Now the unit is slightly to narrow! Maybe I am not looking at it right. I didn’t tighten everything down, it just seemed like more space to take up then normal.
Here is the picture of the original parts that I had to work with. You can see the gap.
And another one of the spacers I had around.
The OEM CB750 one. After thinking about things and looking at the pictures again, I might have things out of order?
The one on the axle in the above picture normally goes into the sprocket carrier side right?
Will have to take another look.
Honestly buy the end of the night it was getting late and I was rather frustrated as this bike seemed to be fighting me at every turn.
i think i would do a mockup leaving out the honda axle spacers
step 2 stringline the wheels to get them inline
step 3 verify cs sprocket is inline with rear sprocket
step 4 measure what length spacers need to be and have a machine shop turn some aluminum spacers or have them turn down what you have,keeping all spacers at least as large diameter as the seely swingarm-fit ones
step 2 stringline the wheels to get them inline
step 3 verify cs sprocket is inline with rear sprocket
step 4 measure what length spacers need to be and have a machine shop turn some aluminum spacers or have them turn down what you have,keeping all spacers at least as large diameter as the seely swingarm-fit ones
without or with tires,i like to wrap it around the rear and run it forward so one each side about a 3rd of the way up from bottom so string has decent length between contacts on rear rim, not so good with a bent rim of courseTexasstar said:
with tars mounted just tape 4 equal spacers in to the rim edge so you clear the tar
then you can eyball/measure to the narrower front rim it is the easiest most accurate method in my ho to quickly verify wheel alignment
getting the rear sprocket inline is an easy secondary operation
butteye have a lathe and mad skills withit 8)
surffly
Over 1,000 Posts
I agree that I need to be more methodical about this.
Like I said, I was very frustrated and just kicked everything to the back of the shop for the night.
Will be back at it tomorrow.
Also on the plate is tune ups on the pile of mini bikes.
Figure there is nothing better then to blow off some steam on one of these.
Like I said, I was very frustrated and just kicked everything to the back of the shop for the night.
Will be back at it tomorrow.
Also on the plate is tune ups on the pile of mini bikes.
Figure there is nothing better then to blow off some steam on one of these.
Tune-A-Fish
BOTM LOSER Proudly Deplorable
surffly said:
Sooo...not to "Jack" again but how does all this relate to the swingarm pivot axle, if I'm no mistake thats 18mm 0r 18 and some change which brings me to the self serving part of my intrusion... I have taken to modifying an R6 swingarm with a ?? HUGE axle and have used the tube from the CB swinger skinned down to slip inside less a thousandths or two for grease of the R6 inside tube while retaining the needle bearings... wheeew. Seem a hot mess, But the mass is basically the same no??
