Topic: 1973/74 cb450 fuel hose routing

[droopy]

anybody have a pic or diagram showing the correct routing?
I lose fuel flow with a gal of gas still in tank.

[dustyc]

I'm sure this isn't the case, but you're aware of the reserve position on the petcock right?

[droopy]

I'm sure this isn't the case, but you're aware of the reserve position on the petcock right?

yep im aware of the reserve position 

it runs fine on reserve but has gal to gal and a half when carbs quit getting fuel

[bill440cars]

       Hey droopy, have ya checked the petcock itself? I'd pull that petcock, disassemble it and make sure that it's clean. might be plugged up. Unless you've already done that.

                                          Take care, Bill

[droopy]

       Hey droopy, have ya checked the petcock itself? I'd pull that petcock, disassemble it and make sure that it's clean. might be plugged up. Unless you've already done that.

                                          Take care, Bill

thanks bill just rebuilt it new seals and filter and cleaned from top to bottom

[bill440cars]

       Hey droopy, have ya checked the petcock itself? I'd pull that petcock, disassemble it and make sure that it's clean. might be plugged up. Unless you've already done that.

                                          Take care, Bill

thanks bill just rebuilt it new seals and filter and cleaned from top to bottom

                               Might have known. Have you tried taking the fuel lines (from the petcock to the carbs) loose & put the petcock in the reserve position to see how far the fuel level would drop? If you do this step, try it with the gas cap down and then pop it open to see if the flow changes. maybe the cap vent is stopped up. Just grasping at straws here.

       

[droopy]

       Hey droopy, have ya checked the petcock itself? I'd pull that petcock, disassemble it and make sure that it's clean. might be plugged up. Unless you've already done that.

                                          Take care, Bill

thanks bill just rebuilt it new seals and filter and cleaned from top to bottom

                               Might have known. Have you tried taking the fuel lines (from the petcock to the carbs) loose & put the petcock in the reserve position to see how far the fuel level would drop? If you do this step, try it with the gas cap down and then pop it open to see if the flow changes. maybe the cap vent is stopped up. Just grasping at straws here.

      

been there done that but will check again  just incase I missed something

[dustyc]

I'm not sure if my 450 still has the gas lines, but I'll look when I get home and post a pic for you if they're there per your original request. 

I hoped you wouldn't think I was trying to insult your intelligence with my first post, but I don't know your background and some of the people I know that have only had modern bikes don't know what a reserve is.

Could you post pics of what you've got to see if any of these keen eyes can spot a problem?

[droopy]

I'm not sure if my 450 still has the gas lines, but I'll look when I get home and post a pic for you if they're there per your original request. 

I hoped you wouldn't think I was trying to insult your intelligence with my first post, but I don't know your background and some of the people I know that have only had modern bikes don't know what a reserve is.

Could you post pics of what you've got to see if any of these keen eyes can spot a problem?

good idea I forgot to take a pic and post it   

dusty It would take more than that to insult me.
and a pic of the left carb fuelhose route would be great right side is obvious as its not more than 2" to 3" in lengh thanks

[droopy]

this is how its currently run I think i need to run leftside carb's fuelhose between the carb's and head  but that still wont fix fuel flow prob right side looses fuelflow first

[dustyc]

Here you go.  I'm not sure how original it is and it seems kind of counter intuitive to run the line down, then back up, but this is how mine's routed.  I'm assuming it's correct because it's got the spring on there and I think that's original.  If nothing else, it's a bump for your post.



Hard to see if you don't know what you're looking for, so I added the arrow.  It's a rubber line with a spring slid over it to keep it from kinking.



Does that look right 450 guys?

[CBGhia]

I'm no 450 guy, but I have never seen a gravity fed system route a fuel line down and then up.   that only works if there is a fuel pump usually.

[dustyc]

Yeah it doesn't seem right.  I'd be asking this same or similar question when the time comes for the 450 to go on the road again.  So whoever gives a definitive answer will be answering my question too.

[droopy]

I fixed it and got the hose routed better that it was 
I pulled the petcock today and found a wasp stuck over the reserve side
must have got in when I filled up last time
I put a half gal gas in it and ran it till it quit and had almost no gas in tank had more gas in crossover tube than tank

[bill440cars]

      That's good to know droopy, that just might make a difference. Also, my 450s don't have fuel lines on them just yet, but the inlets on the carbs are set up to have the lines come DOWN to them. I don't see how they could be correct to come down and turn up to the carbs. That being said though, as long as the fuel supply is higher than the carbs, I don't see why it wouldn't burn all the gas, without a pump. I mean, if the tank IS higher and the outlet of the tank, is on the bottom side, seems like only a small portion might be left in the lines, if any at all. That's the way I see it    

[dustyc]

I'm going to ask over at the Honda Twin site for my own satisfaction.

[droopy]

I'll post a pic of how I ran the fuel lines when I get a chance