Topic: Stripped Screws on My CB750

[AintNoEasyWay]

Hey everyone, looking for your advice on some stripped screws in my carbs. I've been trying to clean them up & rebuild them, but started out using a phillips head screwdriver on the screws. I didn't realize all the screws were JIS at first, so some of the screws have stripped from using the phillips. I've since gotten a JIS driver, but need some method for getting out the stripped screw in the link arm assembly & another down in the throttle slide.

I've tried using screw extractors, but they're not grabbing on the link arm assembly screw & are too short to reach the one down in the throttle slide. I've included photos if that helps. What's the next best course of action? A lot of these screws just seem stuck!

[Kenzo1979]

Screws in these areas aren't usually that frozen.  One trick I use (but haven't tried it on screws this small or in this area) is to get a socket that almost fits onto the head of the screw, then I tap it on there good and tight with a hammer, then turn it off with a socket wrench or bit holder driver.  If it is that frozen, I would soak it in PB Blaster for a day or 2 first.  Have patience, don't do anything irrational like drilling...yet.

[flybox1]

geeze...lots of screw shavings on that top photo. 
JIS screwdrivers usually prevent that, along with PB Blaster, a heat gun or propane torch..

[Mo]

Makes you really wish there was a universal standard. I've had luck with needle nosed pliers in the past. Just grip with the end and twist.

[2wheels]

Looks like one of the screws could be cut into a slot screw with a dremel tool and cut off wheel.

[lucky]

Looks like one of the screws could be cut into a slot screw with a dremel tool and cut off wheel.

Do not do that.
It will just spray metal particles all inside the carb!

[lucky]

I will say this, at least you admit you messed them up. I give you credit for that.
Many just blame it on a previous owner.

The reason these screws get stripped is because of not getting the right tool.
Using a worn out old screwdriver and probably the wrong size. It is not about JIS.

All you would need to do would be to use a #2 phillips screwdriver.
But FIRST you need to remove the carbs from the motorcycle because otherwise you will not get the screw driver on the correct straight down position.

The two screws in the bottom of the slide on the needle holder are #2 phillips also.

You have a real mess now.
On that lifter arm screw I would try to remove it with minature vice grips, New ones that have good teeth.


I know you will order the new OEM screws from Bike Bandit now.
I doubt you would just try to put in any screw that you have laying around and get it cross threaded into the hole.

If you did that then you would want to get a new set of carbs .

I hope you do not throw those carbs in the garbage .
Honda owners really need those parts. There are no more being produced.

[lucky]

Makes you really wish there was a universal standard. I've had luck with needle nosed pliers in the past. Just grip with the end and twist.

Good idea but minature vice grips work better. Gets them out every time.
I hate (thats right) when people strip screws then do not replace them.
They just leave their mess for the next mechanic to clean up.

[lucky]

One more thing beginners,
Do not try to remove the screws in the bottom of the slide on the needle holder until  you have the slide OUT of the carb, so that you can hold it well supported to remove the screws.

[Mo]

The mini vice grip could work too, I just havent seen any that would fit into such a small area. Sounds like a nice tool to own though!

And most of these screws are available readily from Honda for cheap cheap cheap. Don't let impatience get in the way of replacing these with quality parts.

[2wheels]

Looks like one of the screws could be cut into a slot screw with a dremel tool and cut off wheel.

Do not do that.
It will just spray metal particles all inside the carb!

Hey Lucky,  he says he is taking them apart to clean and rebuild.  I'm pretty sure a little more mess at this point is not a big deal.
Also a little paper towel packed down in there will prevent most mess.

[Kenzo1979]

Vice grips come in all shapes and sizes.  You're gonna want needlenose minis.

[AintNoEasyWay]

Thanks for all the replies.  I'm completely new to bikes & mechanics, so I take responsibility for messing things up. That's the only way to learn. I'm trying to do as much research on these bikes as I can & be careful how I proceed. Yes, I've already pulled the carbs off the bike. I've rebuilt one carb entirely with the exception of the throttle valve & new needle (this is the throttle valve with the stripped screw).

New phillips head screw drivers stripped these screws. I've already ordered brand new screws for the carbs, should arrive in a couple days. I definitely don't plan on throwing out the carbs!

Hope this answers some of the comments. Again, appreciate any suggestions you guys have.

[Mo]

..did you get the screw out?! 

[AintNoEasyWay]

..did you get the screw out?! 

Nope, just getting off work. May have to go buy some mini needlenose or a small vice grip. Are there any other techniques out there I might use?

[Vinhead1957]

The easiest method is to drill the head down just enough to pop the head of the screw off. Disassemble then use small vise grips

[lucky]

BTW do you know what a hand held impact driver is?

Make sure you know how to use it.
Many people have one, but do not know how to use it.

[oldschoolcarbs]

http://www.oldschoolcarbs.com/vessel-jis-driver-set/

[AintNoEasyWay]

Alright guys, managed to remove the screw down in the throttle slide last night with a screw extractor. 1 down, 1 to go. As long I've got the right method, I assume the screw on the second carb's link arm assembly should be the easier of the two to remove.

Oldschoolcarbs, that vessel JIS impact driver is the one I ordered earlier this week. Glad I'm on the right track with that.

[bjatwood]

Left threaded/reverse drive drill bit would extract these screws also. Suprised it hasn't been brought up before now.

[chickenman_26]

Hey everyone, looking for your advice on some stripped screws in my carbs.

One piece of advice I'd offer is to not remove screws that don't need removing. The one on the link arm is the synchronizing screw. It should have had a slotted head (not phillips) and a lock nut. Don't try to remove the others if you haven't already. Just remove the bolt securing the link arm pivot to the shaft. After you separate the carbs, the shaft will be out of the equation, and the entire link arm w/slide will just lift out. Then hold the slide firmly in your hand, press a #2 Phillips (JIS preferred) firmly down into the tiny screw head, and hold firm downward pressure while turning the screw loose. It'll take some good pressure till it pops loose. Then remove the other. Don't disassemble the link arms any further than that.

I take responsibility for messing things up. That's the only way to learn.

Actually, no. It's not even a possible way to learn. Thank God brain surgeons don't learn that way. Not trying to be nasty, but you new guys should learn shop skills and best practices on junk parts before attacking critical parts on working machinery. Find yourself a mentor, or this likely won't be your last "learning" experience.



Stu

[70CB750]

LOL, Stu, I worked in a car shop where the owner was just like that.  He would never learn basics such as use cutting oil or any oil on a tap.  With very few exceptions he would snap the tap and than rant on "fark this and fark that and I hate this car,..." 

Amusing for a while, but it was killing me to watch him mess things up.

[AintNoEasyWay]

I take responsibility for messing things up. That's the only way to learn.

Actually, no. It's not even a possible way to learn. Thank God brain surgeons don't learn that way. Not trying to be nasty, but you new guys should learn shop skills and best practices on junk parts before attacking critical parts on working machinery. Find yourself a mentor, or this likely won't be your last "learning" experience.



Stu

Haha. Thanks for the tip on removing only what's necessary, Stu. Learning from mistakes is definitely a possible way to learn; I meant that the only way to learn from mistakes is to admit you made them. Stripping a screw is a lot different than messing up brain surgery 

[Tugboat]

One piece of advice I can throw in here is that screw extractors are by no means the end-all be-all of getting screws out. Usually there's a reason that the screw/bold won't come out. In this case it's a stripped head; but often it's buggered threads, corrosion or the like that's keeping a screw from coming out. In those cases, all the twisting in the world isn't going to get it out - you'll likely end up snapping off the extractor, which is usually hardened and not easy to drill. So use extractors lightly, knowing that if it doesn't come out relatively easy then there's something else at play.

Glad you got the one out - good luck with the other!

[Kenzo1979]

Man, people love this thread.  And to think I could only get one person to chime in on which ebc clutch spring kit to get for my cb550k, hahaha.