Slipping Out of Gear After 3-4K rpms

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Re: Slipping Out of Gear After 3-4K rpms

Postby Fishrider » 22 May 2018, 02:47

Apparently, I have another problem which I just noticed. Oil is leaking from the gear change shaft. It leaks badly only when shifting. This is really frustrating. Had I known that before I wouldn't have put the sprocket back together. I think that is why there was so much gunk in there in the first place. Back to square zero. Starting to think I bit off more than I want to chew. Hopefully its just the oil seal. Any input on the Starting issue is still welcome.
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Re: Slipping Out of Gear After 3-4K rpms

Postby Richard » 22 May 2018, 09:05

For your starting issue I would first check the condition of the battery. I was having the same issue and fixed it with a new one.

For your oil leakage I guess you will have to open up the panel behind your front sprocket to check where its coming from.
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Re: Slipping Out of Gear After 3-4K rpms

Postby Freddy » 22 May 2018, 14:28

Fishrider wrote:The bike will start at full choke, but then dies after about 3-5 seconds. I have to let it sit for a minute before trying to start the bike again or it won't start at all. What are some of the obvious culprits? Keep in mind that I just had the carbs overhauled, new plugs, new carb boots, new petcock, I think a new fuel filter as well. Air filter looks good.

TIA.


If the new petcock is a genuine one, put it in the prime position. Then open, one at a time, the drain screws in the bottom of the carby fuel bowls and watch to see if you have a strong solid and continuous stream of fuel running out. Put a plastic hose on the end of the little 'snouts' and catch the exiting fuel in a fuel can if you want to do it the safe way.

Your checking the best way you can, that there is fuel entering the carburetor bowls. That it dies quickly and you have to wait a bit before it will fire again suggests fuel may be just dribbling into the carby bowls.

P.S. Don't assume that because you've just had the carbies overhauled and fitted a new petcock that these can't be the problem. If the person who overhauled the carbies fitted parts from some of the aftermarket overhaul kits e.g the float valves, this may be the cause of your problem. The old Zephyr Zone was littered with horror stories of problems associated with using non genuine carburetor parts.
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Re: Slipping Out of Gear After 3-4K rpms

Postby Fishrider » 22 May 2018, 16:17

Totally screwed. The metal holder that the gear shifter sits in is broken off the crankcase. Looks like it was punched in from when the bike was dropped. I would need a whole lower casing, or an expert welder. Not to mention all the work. Where was that 6th gear thread again? LOL. So much for riding this summer.
Attachments
Broken Shifter Crankcase Small.jpg
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Re: Slipping Out of Gear After 3-4K rpms

Postby Richard » 22 May 2018, 20:21

O man that IS serious damage! :shock:

Personally I would first try to go the welding way but certainly done by a professional welder. Replacing the lower carter is probably not a good option, maybe finding another engine would be more simple if welding isn't working out...
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Re: Slipping Out of Gear After 3-4K rpms

Postby Swampy » 23 May 2018, 00:00

I feel for you Fishrider… you have not been lucky at all right from the start... A so called mechanic checked this bike over for you and its been bad luck all the way :(
Like others have mentioned best way forward is to try to get it welded....
Hope it all works out for you and keep us up to date plz.
Swamps :)
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Re: Slipping Out of Gear After 3-4K rpms

Postby Freddy » 23 May 2018, 01:20

Fishrider wrote:Totally screwed. The metal holder that the gear shifter sits in is broken off the crankcase. Looks like it was punched in from when the bike was dropped. I would need a whole lower casing, or an expert welder. Not to mention all the work. Where was that 6th gear thread again? LOL. So much for riding this summer.


OK, here's what I'd do if I was in your shoes ........

As others have said, getting it professionally welded is the correct repair. HOWEVER, this requires the engine to be pulled out, sump removed, secondary shafts, clutch and flywheel removal, etc, etc, before even being able to remove the lower case half. Then you need to strip out the gear change mechanism before taking it to the welding shop. Nothing exceptionally difficult in all of this IF you have a well equipped workshop, and some solid experience. Not so long back I did all this to replace some pitted gears, and to be honest I'm glad I'd previously done parts of the exercise e.g new starter clutch, and was familiar with much of it rather than tackle the whole exercise as one first time experience.

So this is what I'd do if I were you ........

Buy some of this .......

Image

The product claims a sheer strength of 3000 psi. All the 'bush' does is hold the end of gear lever rod, with some of load carried by the front sprocket cover. If you buildup the epoxy big time around the external base of the bush I think it may be strong enough, there looks to be plenty of room to build it up. The secret to success will be the cleanliness of the surfaces. All traces of oil will need to be removed, so I'd clean them several times with the strongest solvent your are game to use and still be able to produce children.

In practical and financial terms from your perspective I think this is probably your only viable option. What have you got to loose? A bit of time, and the cost of a pack of 2 part metal epoxy. Use heaps to give it lots of lateral strength making sure the bush is accurately positioned and the internal remains clear.

Stressing again, clean clean clean the surfaces prior to using the epoxy. Success or otherwise will I reckon hinge on this. Done well I reckon you may be able to achieve a quality permanent repair.

Good Luck.
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Re: Slipping Out of Gear After 3-4K rpms

Postby Fishrider » 23 May 2018, 03:07

Freddy, I had a buddy suggest this idea as well. JB Weld claims 800 psi adhesion strength and almost 4000 psi shear strength. I was thinking of machining a small aluminum plate that would butt up against the front side of the holder. Place epoxy underneath the plate and then a solid bead all the way around the holder. That would give some added strength and adhesion area to the rod and the epoxy weld. You can't make the plate or bead too thick because the shaft spring butts up against the crankcase wall. I think their is just enough room to pull off my idea. If it holds for a season then great. If not, back up plans are weld it, engine swap, or it becomes a part out project for Ebay. Most likely number 3 because number 1 and 2 I just don't have the time for.

Even if I pull this off, i still have to get the damn thing started. Sounds like I may have to go back into the carburetor, and I am unhappy about that. Thanks for all the suggestions and good will guys.
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Re: Slipping Out of Gear After 3-4K rpms

Postby Freddy » 23 May 2018, 09:39

This is the reason I would use Locktite 2 part metal exoxy. They are a serious manufacturer of a range of industrial products so have a brand reputation to uphold. I'm not surprised it won the test in the video below

https://www.youtube.com/watch?v=bM4IGweHT2k
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Re: Slipping Out of Gear After 3-4K rpms

Postby Fishrider » 10 Aug 2018, 05:19

Update to my, as yet, unsolved issue of the broken gear shift holder. Here is what i tried so far.

I used JB weld after scuffing up the part and engine and cleaning everything thoroughly. It worked! For 3 circles around the block. Then the weld failed and it got stuck in 2nd gear.

I had a guy come over with a mig welder and some aluminum wire. This was a total failure. We couldn't get the weld to stick fully to the holder or the case. We didn't want to heat up the engine case because of what happened next. We heated the holder, and the holder cracked. We suspect that if we had used argon for cooling while welding we might have done better. Unfortunately, we didn't have any on hand at the moment.

So here are some new options. Any thoughts are welcome.

1) Find an aluminum bushing that is the same size or machine something to fit, and try the weld again with argon or even a tig weld. Although, the guy helping me doesn't currently have a tig. I could maybe find someone else, but it would require taking the engine out and bringing it somewhere.
2) I have done some research on building a carbon fiber layup piece that I can screw into the case. I have a little experience making carbon fiber or fiberglass structures. I am pretty sure I can accomplish this, BUT I am concerned about heat. There are some high temp epoxies out there that allow for working temps of up to 350F after a proper post curing heating process. Still that may be pushing the limit inside an engine that most likely runs into the 300F range. It would cost me about $150 for epoxy and carbon fiber. If the piece fails however, it could shatter possibly destroying the engine.
3) Do an engine swap. There is, at least, one engine on Ebay right now. I am sure if I poked around I could find more. If I did this I almost would be tempted to crack the engines to see which is in better condition and pull parts, but that is a lot more work. There is always the old 6 speed swap, but that is even more work. Sourcing even more parts and spending lots more money.
4) Part out the bike. A slow and painful process, but I suppose I could get half my investment back. New tires, great rims, forks, tank, frame, swingarm, seat, etc etc.

Good Times...
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