Crashed GS550 this morning due to high rpm in throttle! Need some help...

[cloudbreakmd]

Gabe,
Don't take the carbs off. The spring is fine. I checked those carbs when I have them to you to make sure they were not frozen up.
And no, you don't absolutely need to have a push cable.

 

[supergrafx]

New OEM cables are the best quality, and not really more expensive than aftermarket (only a buck or two more). However, they will likely be too long as noted earlier.

Please don't try to ride until this is sorted out -- that dipstick mechanic basically tried to kill you by remote control this morning. Glad you're OK!

Throttle cables are very simple mechanisms, but there's absolutely no room for error.

I've always been able to re-route throttle and clutch cables that end up too long -- you have to experiment and test to find the best position and make sure they don't bind when you move the handlebars.

You'll need to remove the tank and take a look.

I'll remove the tank this weekend and take a look and see about the possible binding. Thank you for the kind comments. It could have been a lot worse. I'm just glad it happened in front of my house and not a busy intersection. I'm not going to ride the bike unfortunatelly until I fix this problem and moreover everything else. Who knows what bolts need to be tightened, ect... I've got lots of time this winter to learn about it and am sure I will have plenty more questions for you guys along the way. Might as well paint the engine too, just to get to know the machine.

Gabe,
Don't take the carbs off. The spring is fine. I checked those carbs when I have them to you to make sure they were not frozen up.
And no, you don't absolutely need to have a push cable.

Navi, if I don't need a push cable, won't I need to manually need to throttle down instead of the throttle snapping back upon release? What Ed is saying makes me think that I need one cable to open and one cable to close the carbs? Sorry for my ignorance, just a little confused. :/

 

[cloudbreakmd]

It's okay to ask questions. No apologies needed.

The push cable is a backup in case your pull cable breaks to spring the throttle back. A lot of people delete that cable anyway. But the throttle mechanism on the carbs are already rigged to spring back to idle is there is no pressure on the mechanism..

 

[tkent02]

Navi, if I don't need a push cable, won't I need to manually need to throttle down instead of the throttle snapping back upon release? What Ed is saying makes me think that I need one cable to open and one cable to close the carbs? Sorry for my ignorance, just a little confused. :/

The cables are nicknamed wrong, there's no pushing. One cable pulls the throttles open, the other pulls the throttles closed. The second one is not strictly neccesary as there should be a fairly stout spring closing the throttles too, normally this works fine. The pull closed cable is just a safety thing, I believe. I don't see any advantage to running only one, but some people do it that way.

At least if the pull open cable breaks you have a spare already there.

 

[supergrafx]

The cables are nicknamed wrong, there's no pushing. One cable pulls the throttles open, the other pulls the throttles closed. The second one is not strictly neccesary as there should be a fairly stout spring closing the throttles too, normally this works fine. The pull closed cable is just a safety thing, I believe. I don't see any advantage to running only one, but some people do it that way.

At least if the pull open cable breaks you have a spare already there.

After what happened today, I am all for having a back up. Even though, and I trust Navi, the spring is good. It makes sense that if Suzuki engineered the cable to have two, then that should be the case. I gave the guy that rebuilt my carbs, two set of carbs, one from Navi which were my bike's original one's and supposably in better shape, and another set which were rebuilt earlier but supposably in worse shape. However, the guy that rebuilt the carbs only gave me three of the carb bodies back from the old set. They were in pieces when I got them back. I got a total of 4 of the carb chambers (the lower fuel basins) back but only three bodies, so I'm not sure what was used, which spring was used, ect., ect, and don't know if the carb parts were mixed base on the condition, ect.... I guess none of this matters now. What has been done, has been done.

 

[supergrafx]

Thanks for the help everyone. I am now leaving for work and don't have internet at home so won't be able to check back with GSR until Monday. Have a wonderful weekend and enjoy yourselves and your bikes!

~Gabe

 

[SqDancerLynn1]

Choke hanging open or miss adjusted can cause high RPM too! Make sure their is some play in both cables

 

[Nessism]

Choke hanging open or miss adjusted can cause high RPM too! Make sure their is some play in both cables

The early 550's did not have a choke cable, just a lever to push on the side of the carbs. Regardless, Lynn has a good point; please check the choke as well to make sure it is not hanging open.

 

[robertbarr]

It makes sense that if Suzuki engineered the cable to have two, then that should be the case.

It's always refreshing to read common sense like this. As opposed to the tiresome game of "let's second-guess the engineers"...

 

[cloudbreakmd]

The cables are nicknamed wrong, there's no pushing. One cable pulls the throttles open, the other pulls the throttles closed. The second one is not strictly neccesary as there should be a fairly stout spring closing the throttles too, normally this works fine. The pull closed cable is just a safety thing, I believe. I don't see any advantage to running only one, but some people do it that way.

At least if the pull open cable breaks you have a spare already there.

Not to argue but I believe I labeled them correctly. Have a read here:
http://www.motionpro.com/tech/articles/throttles_and_throttle_kits/

Next to last paragraph labeled "Notes."

Also check the choke lever. Make sure it's doing what its supposed to. Call me and we can talk.

 

[tkent02]

Not to argue but I believe I labeled them correctly. Have a read here:
http://www.motionpro.com/tech/articles/throttles_and_throttle_kits/

Next to last paragraph labeled "Notes."

Not your nickname, it is the common usage on motorcycles, but there is no pushing.
How can you push with a string?
One pulls open, one pulls shut.

If it was truly push pull, there would be no return spring and only be one cable, like a lawnmower throttle, and the inner would have to be solid stiff wire. Like a lawnmower throttle cable, a solid piece of single strand wire, stiff enough to push. Another example of push/pull is the single steering cable on a motorboat, it uses a very stiff inner cable.
These motorcycle cables are floppy multiple strand wires, and slightly loose in their housings, as they are designed only to pull smoothly, not to push.

Also look at how the outer cable just slides into the adjuster, this cable cannot transmit a push, as the outer cable just pushes out and falls apart.
If you still don't believe it, try removing the cable that pulls the throttle open and go for a ride. Tell me how well the other cable pushed the throttle open.

 

[Nessism]

I agree with Tom, motorcycle cables do not push, they pull.

For some reason the motorcycle industry, at least the one in the aftermarket, holds steadfastly to the mistaken "push/pull" naming convention for the throttle cables in question. Too bad no one is smart enough to stop with this sillyness and rename the cables properly.

As a side note, in that motion pro link they state the following:

"Notes: Do not consider any single-pull throttle (only one cable used) to replace any push / pull throttle (one pull cable and one return cable)."

Key idea here: use a proper TWO cable arrangement for safety.

 

[Suzuki_Don]

Can someone please explain why on the VM carbs we have a pull/pull cable system with two cables and on the CV carbs we have only one throttle cable to pull the butterflies open. Is it that the slides are more likely to jam in the corresponding cylinders where they reside as opposed to a shaft turning in a bore.

On another point and I don't mean to hijack this thread, is there some way to decrease the spring pressure on the CV shafts as I expect the twistgrip will have a heavy feel to it when I get the carbs assembled back on the bike .

EDIT: Fruedian slip I Think.

 

[supergrafx]

I inspected the throttle cable under-neath the gas tank this weekend. The mechanic that supposably serviced my bike made it easy as I was shocked to find the previous bold that kept the gas tank attached to the bike's frame missing?!? Perhaps the gas tank missing it's bolt to the frame caused the binding in the throttle cable since the gas tank must have been moving much more left to right as I made a turn without the bolt present. Well, I'll stop complaining and give forth the pics to my findings:

I also noticed that the breather hose that attaches to airbox from the engine's cylinder head was loose and not attached, something I had previously discussed with the would be mechanic, but probably not reattaching. I fear now that reattaching this hose will make the sync job that was given to my carbs, out-o-sync...

I still have been unsuccessful in finding the 1979 gs1000s throttle cables. I followed the link to motion pro's site and see that they make custom cables? I will write them an email. Perhaps 4 inces less than stock? The throttle cable I have now is stock, with the digits: (47001_3-38-A) on the cable. In the parts the previous PO gave me when getting the bike, I found an identical cable with the same part number that must have been the bike's return cable. The metal wired stand within the cable seems a little damaged though.

 

[cloudbreakmd]

Reattaching your breather hose will not affect your carb sync.

 

[tkent02]

Not sure on your exact model, but having the cable go over that wire loom hook, and over the tank front mount rubber looks incorrect, will probably leave a very sharp bend, easily kinked farther up near the steering head. The cable should go between the frame rails above the carbs, then go under the tank mount rubber and through the fork legs in between the upper and lower triple clamp to the right of the steering head.. out between the guages and the bars and out parallel to the bars to the throttle grip.

It is this type of thing you are looking for, incorrect routing will cause problems...

Look for the correct cable routing in the Suzuki manual, and inspect your cable for any kinks or damage in the steering head area.

The missing tank bolt won't cause this problem, but is hazardous in itself, if a shop did that they are morons.

Get the cable routing right, this is serious.

Your clutch cable is all boogered up too.

 

[robertbarr]

Are those home-made headlight ears? Curious.

That has to be the oddest clutch cable routing I've ever seen, and I kind of wonder how it even works (although I'm sure it does).

 

[cloudbreakmd]

Peter bought the headlight ears off of Fleabay. I suggested the cut inner tubes to keep them from scratching the fork tubes. The clutch cable and throttle cables were routed funny because of the clip ons.

 

[Big T]

That throttle cable is wrong in so many ways.

AS Tkent mentioned, in photo #2 the cable runs between the frame rails (where all the wires are) behind the coil for a straight shot from the back of the coil to the carbs. You can see where the tank rubs on it where it runs outside the frame rail.

At the front, the loop back is too tight, causing a kink.

I'd suggest getting throttle cables for a 1979 GS1000S, which is what I did when I put lower bars on. They're at least shorter than stock.


It's a shame so many hacks have worked on this bike. Keep posting up your problems and they should get resolved before good weather comes.

 

[cloudbreakmd]

Gabe,
You'll be fine. We'll all help you if you're willing to turn the wrench. I wish I had finished the bike prior to Peter finishing it himself