cb360 Finished bracket for sagging carbs

[trek97]

My new pliable boots are causing my carbs to sag. maybe making my bike run richer. I needed a support. I looked at it for 10 minutes. took a break. another 5 minutes...and BAM. there is a little square cast into carb between filter and bowl, AND a motor mount directly under.
It wont hinder filter installation or bowl removal. It will add one more step to carb removal, cause you gotta get it out of the way to pull carbs...but its only one bolt.
I made it from a scrap piece of flat, drilled a hole cut w chopsaw, bent it, filed edges, and primed it...10 minutes. I believe its gonna work great. when installed it raises both carbs to level...if I do need to make one for left it will be a little trickier. but basically the same, a little longer, drill a hole in mount, and bent a little differently.

I do need to add PJs name to this...
Saturday while i was trying some new jetting I found I had a rich condition. Thats when i noticed carbs sagging.
i worte PJ and asked what he thought of sagging carbs...He confimed my theory, It may lead to a rich condition.
I asked him if he had a fix...he said he temporaried carbs w a bungee cord...and used springs as a permanent fix.
I havent seen his spring idea...so it may very well be a better solution than my brackets.

In primer for pics...so you can see it better...will be black.

The little notch in the end "traps" it in carb casting so it cant work out sideways. Maybe add a little piece of rubber to end to insulated it, if I see wear in carb casing.

Finished support. with insulator made of fuel line, painted black and installed. I am pretty happy. I dont notice it at all.

Here it is installed...right down there behind the kick starter.

and I rode several miles today...it did not vibrate loose, or cause any other problems.

 

[Captmilk76]

Re: cb360 prototype bracket for sagging carbs

Would it vibrate loose after a long ride?

Sliced in by my Droid Razr

 

[trek97]

Re: cb360 prototype bracket for sagging carbs

I thought about that. If vibrating loose becomes a problem you would just need to place a star lock washer between the bracket and the motor mount. That will keep it from turning.
And if the motor mount vibrates loose...i think you have bigger problem than sagging carbs.

 

[Flugtechnik]

Re: cb360 prototype bracket for sagging carbs

I think he meant might the top slide aft off of the carb.

I'm guessing when you put the filter on it will be trapped.

 

[Sonreir]

Re: cb360 prototype bracket for sagging carbs

My carbs ended up sagging completely out of the boots (extra weight from the stacks) and allowing air in. I made a hangar from the top out of some water heater straps.

 

[trek97]

Re: cb360 prototype bracket for sagging carbs

heres the star washer I was talking about. Place it between the bracket and the motor mount. Not under the bolt head, apply a drop of purple lock tite or thread sealant to keep bolt from galling or vibrating loose, then tighten to torque specs. Im 99.9 % sure this is the last thing that will vibrate loose on your bike. Also being secured to the engine mount...and carbs being secured to engine. If there is any flexing, wiggling or bouncing going on there that might cause carb insulators any undo stress. You may have a bigger problem than sagging carbs. Also as I mentioned in original post I may add a peice of rubber to end of bracket to insulate carb body from wear caused by vibration. Like the title states "prototype".

 

[trek97]

Re: cb360 prototype bracket for sagging carbs

My carbs ended up sagging completely out of the boots (extra weight from the stacks) and allowing air in. I made a hangar from the top out of some water heater straps.

Thanks Sonreir...can we see a detailed pic, how did you secure it to frame and also carbs.
Is it easy to remove and install for carb work?
does it effect filter, bowl or carb top removal while carbs are installed on bike ?
and least important, to some, How does it look when installed? or can you even see it (hidden between carbs)
Basically Id like to see if its a better idea than mine...if it is i will scrap mine. and go with your idea.

 

[Sonreir]

Re: cb360 prototype bracket for sagging carbs

I'll take some pics later... this is the closest thing I have, right now.

You can just make out the strapping behind the frame. For what it's worth, my method may not work unless you're running stacks as the frame may get in the way of bringing the strap closer to the carbs.

 

[trek97]

Re: cb360 prototype bracket for sagging carbs

OK, here is what I have done...cut the notch a little wider, bout 1/4 inch. Slit a small peice of fuel line and snapped it in notch. so it insulates between carb body and bracket. maybe post a pic later.
Also it cant slide off the carb...the notch in bracket has it trapped in the little square on the underside of carb casting between bowl and filter.

Now there is a small piece of rubber fuel line trapped between the two also, not in this pic

 

[popssss]

Re: cb360 prototype bracket for sagging carbs

I have a set of carb mounts from a cb550, and when I get home I'll see if maybe they can be used.

The rubber mounting system now relies too much on the airbox mount to the frame to hold everything, but there is another rubber tube from the airbox to the carb as well.

SO the carb sits between these two flimsy rubber tubes, one side pressure fitted to the engine the other end pressure fitted to the airbox.

if I get a picture of what I did to hold the stock air filter to the carb-to-air cleaner tube, I'll post it.

 

[trek97]

Re: cb360 prototype bracket for sagging carbs

Finished support. with insulator made of fuel line, painted black and installed. I am pretty happy. I dont notice it at all.

 

[trek97]

Re: cb360 prototype bracket for sagging carbs

I have a set of carb mounts from a cb550, and when I get home I'll see if maybe they can be used.

The rubber mounting system now relies too much on the airbox mount to the frame to hold everything, but there is another rubber tube from the airbox to the carb as well.

SO the carb sits between these two flimsy rubber tubes, one side pressure fitted to the engine the other end pressure fitted to the airbox.

if I get a picture of what I did to hold the stock air filter to the carb-to-air cleaner tube, I'll post it.

Id like to see what you came up w Pops, thanks.

 

[Sonreir]

My only concern with the "under the bottom" approach is if vibrations get quite intense. Possible that the carbs will bounce out of the bracket?

Anyway... here's the solution I came up with. Cost me a couple of bucks in hardware, though it is scratching up my stacks a bit. meh.

http://youtu.be/7qOhtZ1OhDI

 

[trek97]

My only concern with the "under the bottom" approach is if vibrations get quite intense. Possible that the carbs will bounce out of the bracket?

I dont really see "bouncing out of the bracket" as too big an issue. the roads you ride must be rougher than mine. If they bounce that much I think they would literally be falling off my bike.

 

[trek97]

Also, you could glue a piece of sheet rubber to your plumbing strap to help w scratching up your stacks.

 

[trek97]

Swivel brought up a great point at 4:27 this morning. I thought I was the only one up at that time. any way he wrote...

I think the support will feed vibes from the motor at high revs and cause foaming in the gas in the bowls,it could affect the fuel mixture and tuning.Vibes and bumps could cause the carbs alloy bodies to crack.There are reasons carbs are all rubber mounted and supported.

Thanks Swivel for the input....So here is my solution, WAY better vibration isolation and heat insulation...cause, that motor mount gets warm.

THE CLEAR TUBING IS JUST FOR EXAMPLE PICS. I WILL BE USING THICKER, REINFORCED, ABRASION RESISTANT OLD SANDBLASTER HOSE. THAT FITS MUCH TIGHTER. NO WIGGLING OFF.

SO, now it will take you about 20 minutes to make and install this bracket...and I am still doing it for "free" w scraps I have laying around garage.

and let me add this,
My intentions for this bracket really isnt to support the weight of the carbs so much, as it simply helps to prevent the carbs from "working" up and down it the manifolds. Thus preventing gravity from pulling on the carbs to start with. thats all.
Sonrier may need more support, because he is using the stacks, adding more leverage to his boots, thus creating more working action.

 

[trek97]

once I got hose shoved onto bracket i had to trim the notched end of hose to better accommodate the carb casting. but all in all everything appears good. So we need to add 20 seconds to the build.
I cant think of anymore concerns right now. still no interference w filter, bowl,fuel line installation or removal.

 

[Captmilk76]

I have been reading this thread and I love the NOS can idea.... Those Harley guys will pull up next to you and say WTF? NOS? and it will be totally worth all the effort.