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Discussion Starter · #1 ·
I recently rebuilt a honda cm450e and replace the old stuck choke cable with a new pull cable that works great. Only thing is the choke pull won't stay out when cold starting. It wants to spring back into the close choke position. I did recently rebuild the carb including rejetting to a cone air filter setup. My first thought is the spring that connects the choke cable to the carb is out of adjustment some how constantly pulling the choke in. I have checked this and it seems good at first sight. Also seems like the carb wants to suck the choke in perhaps via a vacuum effect. Is it possible to adjust the carb so that the choke won't stay out on cold start? Perhaps someone with more knowledge than I do can explain what the dynamics in play are here?
 

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I'm not sure about the 400/450 SOHC series, but the bikes I had with OEM choke cables back in the day (GL1000 comes to mind) had a rubber-covered round knurled nut on the base of the cable mount that allowed you to tighten it a bit to provide friction to hold the choke cable up while the bike was warming up, and you could adjust that friction tension if you wanted it tighter. If you bought an aftermarket cable you probably didn't get that advantage. I can't find a listing for an OEM choke cable for the CM450e on cmsnl.com
 

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Did you reinstall the little bracket that holds the metal part of the choke cable to the carb bracket? If not your whole cable will just pull and then slide back
 

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AD is correct. The OEM choke cable has a plastic base which can be tightened to increase friction on the cable.
 

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Discussion Starter · #5 · (Edited)
So it sounds like I'm missing a little friction in my life:grin: Honestly I just installed the cable exactly the way the old one came off. The new one is pretty nice but has near zero % friction. The carb can easily pull it back in without much force. I'll look in to ways to create friction or reduce the spring back force from the carb bracket.

80cb400t- I did reconnect that carb end bracket to the stationary part of the cable, but it may be worth checking it to make sure it didn't work lose or something. Kind of hard to get in there and tighten the screw!

Best photo I have of the cable connection on carb. the cable end goes into the round part of the bracket. The bracket is connected to a shaft and torsion spring. I think I could reduce the tension on the spring similar to a wind up clock. I also wonder if a small shaft collar placed on the cable could add some tension. They make them with little set screws that can be carefully tightened to adjust tension around a shaft shaped object.
IMG_2526.JPG
 

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Brian, I think it's the cable you bought. I tried to find a picture of the OEM choke cable yesterday but couldn't, even in the fiches at cmsnl.com. It's a rubber-covered (to keep water out of the inner cable) round nut at the base of the cable at the bracket up top where it mounts, right below the knob you pull when the choke is off and the knob is all the way down. Not sure if they look the same or similar to the older Gold Wing choke cables, but it doesn't have anything to do with the end that mounts on the carbs and connects to the choke mechanism there. It's about friction applied to the rod below the knob as you pull out the choke (the rod that ultimately is attached to the inner cable). The red arrow points to the rubber dust/water cover over the nut that can snug the cable movement. Is this one from DCC the cable you bought?

choke cable.jpg
 

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Discussion Starter · #7 ·
Brian, I think it's the cable you bought. I tried to find a picture of the OEM choke cable yesterday but couldn't, even in the fiches at cmsnl.com. It's a rubber-covered (to keep water out of the inner cable) round nut at the base of the cable at the bracket up top where it mounts, right below the knob you pull when the choke is off and the knob is all the way down. Not sure if they look the same or similar to the older Gold Wing choke cables, but it doesn't have anything to do with the end that mounts on the carbs and connects to the choke mechanism there. It's about friction applied to the rod below the knob as you pull out the choke (the rod that ultimately is attached to the inner cable). The red arrow points to the rubber dust/water cover over the nut that can snug the cable movement. Is this one from DCC the cable you bought?

View attachment 260912
Yeah that sounds about right. I'll have to examine the pull cable closer but I think a shaft collar around the cable pull knob would squeeze the choke and add friction. Though i"m not sure if there is room to fit around the rubber cover area.

View attachment 9746T11.pdf
 

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I get what you're saying, but the cable from DCC has the round friction nut already on it at the top, covered with a rubber cap to keep water out of the cable as well. I realize you already bought the one you have, but I've bought my share of stuff that I thought would work on my 450 and ended up getting something better instead. Just a thought
 

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The tension control knob is plastic on plastic so don't add any kind of locking fluid there. Yes, the tension will loosen a bit over time as the tensioning pieces wear down and maybe with vibration.
 

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Discussion Starter · #12 ·
Perhaps pipe thread tape would help keep it, but also allow for easy removal and adjustment down the road. That nut needs to be like those nylon self locking nuts with the plastic in them. At least mine is pretty lose. Don't really see how it's expected to stay with bike vibration.
 

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It should just turn until snug enough to hold the cable, I've hardly ever needed to adjust the tension on mine over the years.
 
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