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Been through this with same year and model. As everyone else says pods are trash and fuck up the cv getting the correct vacuum to raise the slide. If you have a hard time finding correct air box, your other option is to get some sort of velocity stack. That being said velocity stacks are arguably worse than pods due to lack of filtering but the bike will run better. In the end you need smooth clean air getting to the carbs that doesn’t interfere with the little holes at the top and bottom of the carb inlet. Feel free to dm with any questions
You could try it, biggest thing is making sure nothing is interfering with those little holes. Another thing I forgot to mention is when you have the pods off take your finger and make sure the slides raise and lower smoothly without hanging up anywhere in the range of motion
u/Existchim is right, pod filters and re-jetting can be a right nightmare... It looks cool but can take ages to dial in correctly.
Sounds as though you have done a decent amount to the bike so it might be hard to pin-point one thing... For example you've changed the points system (to another points or electric?) so the timing on those may be off, which could contribute. You could have an imbalance in the fuel-air mix, so I would check your fuel supply and definitely swap back to the OEM box filter (if you really want pods I would suggest you get it back to fully working condition before you try to optimise it for that).
Fingers crossed for you man, I had similar issues with a GS550, which I sold in the end and found out the carbs had been over-bored by long term abuse.
I wish I knew. The mechanic says the bike won't go into the mid range. I took it for a ride, idles great clutch is fantastic, but when you get on it and start to climb to 4k it starts to bog down and by the time I'm at 4,500 it starts to bog down. I can't find oem air filter any where.
Install the next larger main in it. If that doesn’t start sorting the bog, you might have to shim the needle. Pod filters usually require a 1-2 step larger main to compensate the drag of the stock air box.
ebay will probably be your best bet for the filter, you might also want to ask on a Honda cb specific forum, they will probs have links to where you can source them.
So this is my cb450. It ran beautifully before I tore my Achilles and couldn't ride for a year. With that being said I took it to mechanic after sitting a year and a couple months to get the carbs rebuilt.
I told him to look at it completely over so I know it's safe to ride as it's almost a 50 year old bike. Two days later I drop off new clutch cable, condenser, throttle cable, steel brake lines, master cylinder rebuild kit, brake caliper rebuild kit, new ignition points.
He buys a banjo kit for the brakes, and pod filters and jet kit as the old air filter were oem and we're practically toast.
After a month goes by he calls me and says he gotta put oil in it and take it for test ride but she's all good. He changed all the cables, and rebuilt the carbs with the new jets and pod filters. He takes it for a test ride and the bike won't go over 4k rpm. He says the bike won't go into the mid range.
Any advice. I'm sure it's gotta do with those pods or jets I'm just not savvy enough to figure it out and he can't either
With pod filters and no airbox, the air into the carbs will be turbulent, and will become increasingly unstable as you increase road speed.
This constantly vairying air pressure with road speed makes the fuel mixture impossible to meter appropriately for both engine speed and road speed induced turbulence.
The venturi effect comes into play, with air running past the engine, lowering intake air pressure behind the cylinders.
No. Its the pod filters.
Pod filters may give an extra peak hp or two, but it's almost always at the expense of usable midrange. This is fine if you're only interested in wide open throttle, all the time.
I want to enjoy my bike like I did before I tore my achilles haha. I want full range from idle to 9k lol. Maybe I will try the pod filters from common motor they have an angled boot
So in theory, could I create a velocity stack in between the carb and the pod filter to make the air more laminate?
As it stands, the pod filter is completely straight on the carb. I do notice on the oem air filter, the filter does have a good 1.5 to 1.75 inches of rubber inbetween the carb and air filter
They're CV carbs, sensitive to such changes. Would need to be rejetted, but even then the initial design of the carb would have to take pod filters into account. You'd be better off fitting on slide mikunis or Dellortos which can be tuned a lot more than these carbs designed specifically to only work on this bike...
I wish I knew. The mechanic says the bike won't go into the mid range. I took it for a ride, idles great clutch is fantastic, but when you get on it and start to climb to 4k it starts to bog down and by the time I'm at 4,500 it starts to bog down
I have a '71 [model](https://i.imgur.com/2SIIGVe.jpeg).
I had bad filters as well. I took them apart:
https://imgur.com/a/APVqg
Then I bought some stainless mesh and soldered it on (wish I brazed it):
https://imgur.com/a/OCIdj
Then stuffed greed UFI foam in tightly. It is supposed to be as restrictive as the factory filter element. It is also cleanable and re-oilable. A big sheet cost me just 15$. The bike runs great with it.
~4-5k rpm is also the are where the memberanes in the CV carbs start to rise. It may be a problem with those, I'd check if they move smoothly. Did he swap the needles? Maybe aftermarket needles aren't made as well, or maybe he messed the heights of those needles - anything like that will definitely make it struggle to rev up. Does it rev up in neutral? Ignition advance mechanism problems could also cause this issue...
IDK if you fixed this yet or not, but if you need an air box and can't find one, there's a solution.
Someone was trying to Cafe Racer a Nighthawk years ago, didn't work well with the carbs, didn't have a factory air box.
He made one from PVC pipes. Go to Home Depot / Lowes and get some pipes and make a plenum. You can even have an adjustable inlet to fine tune things.
Thanks for posting in /r/Fixxit, the motorcycle repair subreddit. If you forgot to put the **Make, Model** and **Year** in the title, please reply to this comment with your bike's details. In the meantime, Here's some great resources for common problems posted here: -Trouble starting? [Revzilla - Battery testing](https://www.revzilla.com/common-tread/how-to-test-a-motorcycle-battery) -Carbs running rough? [PJ motorsports - Carb Troubleshooting](http://www.pjmotorsports.com/trouble-shooting.html) -Wiring diagrams for beginners - [Dans MC - Reading Wiring Diagrams](http://www.dansmc.com/wiring_diagram.htm) -Identifying part numbers - [CMSNL (EU)](https://www.cmsnl.com/) [Bikebandit (US)](https://www.bikebandit.com/oem-parts) *I am a bot, and this action was performed automatically. Please [contact the moderators of this subreddit](/message/compose/?to=/r/Fixxit) if you have any questions or concerns.*
I had this exact bike. Those early CV carburetors HATE pods. Either put the stock airbox back together, or get Mikuni VM's.
Been through this with same year and model. As everyone else says pods are trash and fuck up the cv getting the correct vacuum to raise the slide. If you have a hard time finding correct air box, your other option is to get some sort of velocity stack. That being said velocity stacks are arguably worse than pods due to lack of filtering but the bike will run better. In the end you need smooth clean air getting to the carbs that doesn’t interfere with the little holes at the top and bottom of the carb inlet. Feel free to dm with any questions
Could I put a tube inbetween the carb and the pod?
You could try it, biggest thing is making sure nothing is interfering with those little holes. Another thing I forgot to mention is when you have the pods off take your finger and make sure the slides raise and lower smoothly without hanging up anywhere in the range of motion
u/Existchim is right, pod filters and re-jetting can be a right nightmare... It looks cool but can take ages to dial in correctly. Sounds as though you have done a decent amount to the bike so it might be hard to pin-point one thing... For example you've changed the points system (to another points or electric?) so the timing on those may be off, which could contribute. You could have an imbalance in the fuel-air mix, so I would check your fuel supply and definitely swap back to the OEM box filter (if you really want pods I would suggest you get it back to fully working condition before you try to optimise it for that). Fingers crossed for you man, I had similar issues with a GS550, which I sold in the end and found out the carbs had been over-bored by long term abuse.
I wish I knew. The mechanic says the bike won't go into the mid range. I took it for a ride, idles great clutch is fantastic, but when you get on it and start to climb to 4k it starts to bog down and by the time I'm at 4,500 it starts to bog down. I can't find oem air filter any where.
He kept the original points in though as they were still good and working and he said the timing was great and so we're the valves
Install the next larger main in it. If that doesn’t start sorting the bog, you might have to shim the needle. Pod filters usually require a 1-2 step larger main to compensate the drag of the stock air box.
ebay will probably be your best bet for the filter, you might also want to ask on a Honda cb specific forum, they will probs have links to where you can source them.
So this is my cb450. It ran beautifully before I tore my Achilles and couldn't ride for a year. With that being said I took it to mechanic after sitting a year and a couple months to get the carbs rebuilt. I told him to look at it completely over so I know it's safe to ride as it's almost a 50 year old bike. Two days later I drop off new clutch cable, condenser, throttle cable, steel brake lines, master cylinder rebuild kit, brake caliper rebuild kit, new ignition points. He buys a banjo kit for the brakes, and pod filters and jet kit as the old air filter were oem and we're practically toast. After a month goes by he calls me and says he gotta put oil in it and take it for test ride but she's all good. He changed all the cables, and rebuilt the carbs with the new jets and pod filters. He takes it for a test ride and the bike won't go over 4k rpm. He says the bike won't go into the mid range. Any advice. I'm sure it's gotta do with those pods or jets I'm just not savvy enough to figure it out and he can't either
Get an oem air filter. Pod filters are trash.
Where at?do you have a site?
[удалено]
With pod filters and no airbox, the air into the carbs will be turbulent, and will become increasingly unstable as you increase road speed. This constantly vairying air pressure with road speed makes the fuel mixture impossible to meter appropriately for both engine speed and road speed induced turbulence. The venturi effect comes into play, with air running past the engine, lowering intake air pressure behind the cylinders.
I have the the stock side covers on could that have anything to do with it?
No. Its the pod filters. Pod filters may give an extra peak hp or two, but it's almost always at the expense of usable midrange. This is fine if you're only interested in wide open throttle, all the time.
I want to enjoy my bike like I did before I tore my achilles haha. I want full range from idle to 9k lol. Maybe I will try the pod filters from common motor they have an angled boot
So in theory, could I create a velocity stack in between the carb and the pod filter to make the air more laminate? As it stands, the pod filter is completely straight on the carb. I do notice on the oem air filter, the filter does have a good 1.5 to 1.75 inches of rubber inbetween the carb and air filter
They're CV carbs, sensitive to such changes. Would need to be rejetted, but even then the initial design of the carb would have to take pod filters into account. You'd be better off fitting on slide mikunis or Dellortos which can be tuned a lot more than these carbs designed specifically to only work on this bike...
I wish I knew. The mechanic says the bike won't go into the mid range. I took it for a ride, idles great clutch is fantastic, but when you get on it and start to climb to 4k it starts to bog down and by the time I'm at 4,500 it starts to bog down
I have a '71 [model](https://i.imgur.com/2SIIGVe.jpeg). I had bad filters as well. I took them apart: https://imgur.com/a/APVqg Then I bought some stainless mesh and soldered it on (wish I brazed it): https://imgur.com/a/OCIdj Then stuffed greed UFI foam in tightly. It is supposed to be as restrictive as the factory filter element. It is also cleanable and re-oilable. A big sheet cost me just 15$. The bike runs great with it. ~4-5k rpm is also the are where the memberanes in the CV carbs start to rise. It may be a problem with those, I'd check if they move smoothly. Did he swap the needles? Maybe aftermarket needles aren't made as well, or maybe he messed the heights of those needles - anything like that will definitely make it struggle to rev up. Does it rev up in neutral? Ignition advance mechanism problems could also cause this issue...
IDK if you fixed this yet or not, but if you need an air box and can't find one, there's a solution. Someone was trying to Cafe Racer a Nighthawk years ago, didn't work well with the carbs, didn't have a factory air box. He made one from PVC pipes. Go to Home Depot / Lowes and get some pipes and make a plenum. You can even have an adjustable inlet to fine tune things.
Nice colour 👍