OzVMX Forum

Clubroom => Tech Talk => Topic started by: pecrazy on November 20, 2016, 08:54:08 am

Title: Is there a way to fix this.
Post by: pecrazy on November 20, 2016, 08:54:08 am
Assembling this IT200, picked up the kick starter shaft and saw this, must have been stripped for awhile but as I never really rode the bike I can't say for sure.  Has a spline on both parts and is just a stopped to stop the lever when it comes back up to it's normal position. It is internal in the case halves so if it fails it is a full strip to fix it.(http://i1380.photobucket.com/albums/ah196/plymoth1/IMG_2178_zpsio2o60pf.jpg) (http://s1380.photobucket.com/user/plymoth1/media/IMG_2178_zpsio2o60pf.jpg.html)(http://i1380.photobucket.com/albums/ah196/plymoth1/IMG_2179_zpsylnllq3s.jpg) (http://s1380.photobucket.com/user/plymoth1/media/IMG_2179_zpsylnllq3s.jpg.html)
Title: Re: Is there a way to fix this.
Post by: pokey on November 20, 2016, 10:49:21 am
If the splines still hold I would be tempted to silver solder it.
Title: Re: Is there a way to fix this.
Post by: shelpi on November 20, 2016, 12:35:17 pm
If the splines still hold I would be tempted to silver solder it.
yep and or tig
Title: Re: Is there a way to fix this.
Post by: crossedup2 on November 20, 2016, 08:18:18 pm
Use a tig. Less heat spread. Don't be temped to weld all way around. And that only if the spline holds the stop plate.

Peter B
Title: Re: Is there a way to fix this.
Post by: pecrazy on November 20, 2016, 08:23:48 pm
Splines are gone, far too much heat to tig or braze it, thinking solder is the way to go, only if it fails it is a full case strip to fix.
Title: Re: Is there a way to fix this.
Post by: 80-85 husky on November 20, 2016, 09:01:08 pm
go back to square 1...fix it properly now
Title: Re: Is there a way to fix this.
Post by: Moto on November 20, 2016, 09:11:04 pm
Solder is too soft and not strong enough.You would need a lot of heat to solder it.    TIG.
Title: Re: Is there a way to fix this.
Post by: TT5 Matt on November 21, 2016, 02:31:52 am
those splines on the shaft look like they have copped a few kickbacks in its life and torn a lot of the splines, the best solution is replace it with a new part and save the head fork of having to do the job twice. have a look at where the stopper has been hitting on kick back mode, there could be some damage there as well
Title: Re: Is there a way to fix this.
Post by: Lozza on November 21, 2016, 07:25:48 am
2 Options best and cheapest is to laser weld with a 312 stainless filler wire,next is to tig it with 312 stainless filler wire
Title: Re: Is there a way to fix this.
Post by: Tomas on November 21, 2016, 08:14:27 am
http://www.ebay.com/itm/YAMAHA-KICKSTART-SHAFT-82-85-YZ125-1984-1986-IT200-KICK-AXLE-39W-15660-00-00-/272350789130?hash=item3f695f3e0a:g:1XQAAOSw9NdXvJEB&vxp=mtr
Title: Re: Is there a way to fix this.
Post by: shelpi on November 21, 2016, 11:00:44 am
of course you could buy a new one! but that would take all the fun out of it
Title: Re: Is there a way to fix this.
Post by: Momus on November 21, 2016, 11:21:48 am
Tig 360 degrees and relieve the case with a chamfer. That shaft wont fail from heat or a weld line crack.
Title: Re: Is there a way to fix this.
Post by: Slakewell on November 21, 2016, 02:25:14 pm
Whilst Im first to get the TIG out , I go with silver solder on this repair. You need capillarity attraction to get in there.
Title: Re: Is there a way to fix this.
Post by: shelpi on November 21, 2016, 03:00:45 pm
Whilst Im first to get the TIG out , I go with silver solder on this repair. You need capillarity attraction to get in there.
agreed
Title: Re: Is there a way to fix this.
Post by: pecrazy on November 21, 2016, 08:51:28 pm
Shaft is hollow and quite thin in that area. I have heard they had a habit of braking, so guessing any heat at all is going to weaken it. If it wasn't internal and a complete case split I would try it but for $116 for peace of mind it's worth it.
Title: Re: Is there a way to fix this.
Post by: GMC on November 21, 2016, 11:57:21 pm
Laser weld?  Cheap?
I don't think so Tim
The only laser welders I know of are all CNC controlled and take ages to set up, they're not for one offs
I may be out of touch but I haven't heard of any hand held laser cutting or welding torchs as they require sending the beam via mirrors.

If the splines are stripped then I wouldn't bother welding it, welds don't like situations like this when there is torsional stress and the hit home on the return won't do it any favours either, this is why Yamaha designed it with the splines to take the load.
If the splines still hold then a weld would be fine to stop the part moving sideways on the shaft
Title: Re: Is there a way to fix this.
Post by: OverTheHill on November 22, 2016, 08:41:41 am
not sure if anyone has mentioned it but the 'very' important thing is to set it on the right spline or your return spring tension will be up the creek. Might get away one spline either way--but!!. On my 490 of which they have a habit of breaking those stops [i think] because they're made of cast crap compared to old model Yam's that appear stamped out material--so--long story long--i found earlier type stops in my junk on old AG175 type shafts. Put in the lathe & machined the swaged over  bit then removed it & fitted the 490 perfect [same quick spline] then bronzed it on. was on tight on the quick spline but bronzed to keep it there. The spline is cut in the direction so it bites tighter on the return against the stop rather than trying to get off when it bumps to a stop. Anyway all that's irrelevant if ya spline is poked except a good [Agy type] stop might bite on whats left on the shaft. On second thoughts looking back at ya pic, there aint much left of the spline. We used to have a great guy at mig welding who would make a beautiful job of fitting that back on--then he retired bugger it. I've got an IT200 too so maybe i should be worried lol.
Title: Re: Is there a way to fix this.
Post by: Lozza on November 22, 2016, 04:27:23 pm
Laser weld?  Cheap?
I don't think so Tim
The only laser welders I know of are all CNC controlled and take ages to set up, they're not for one offs
I may be out of touch but I haven't heard of any hand held laser cutting or welding torchs as they require sending the beam via mirrors.


Laser welders are portable and hand controlled jewellers use them all the time. Most laser welding shops just charge an hourly rate and they can do LOTS of work in an hour.
https://www.youtube.com/watch?v=25pDxYrMFA0

hand held torch
https://www.youtube.com/watch?v=xbiXeAORkeQ

2min per end cap
https://www.youtube.com/watch?v=yuTIR5E98Dw
Title: Re: Is there a way to fix this.
Post by: pecrazy on November 22, 2016, 04:58:09 pm
Best way to fix this is a new one, if it was no longer available I would consider soldering it. Overthehill you are correct, I have already set it up and marked it where I thought the right amount of spring tension was.
Title: Re: Is there a way to fix this.
Post by: djr on November 22, 2016, 08:48:14 pm
I have Mig welded one of these about 3 years ago , and it is still working today.
I would have preferred to fit a new one or Tig weld it but I was desperate to get it fixed and ride the bike
{ we have all been guilty of some nasty repairs when desperate to ride, I imagine }
Title: Re: Is there a way to fix this.
Post by: 80-85 husky on November 22, 2016, 10:15:57 pm

we have all been guilty of some nasty repairs when desperate to ride, I imagine }



OOOOOHHHH YYYEEEAAAHHH :o
Title: Re: Is there a way to fix this.
Post by: Momus on November 22, 2016, 11:48:23 pm
Shaft is hollow and quite thin in that area. I have heard they had a habit of braking, so guessing any heat at all is going to weaken it. If it wasn't internal and a complete case split I would try it but for $116 for peace of mind it's worth it.


Everytime you jump in a rear wheel drive car the 360 degree welded tailshaft yokes are also quite thin but work reliably.
Title: Re: Is there a way to fix this.
Post by: shelpi on November 23, 2016, 11:12:57 am
Best way to fix this is a new one, if it was no longer available I would consider soldering it. Overthehill you are correct, I have already set it up and marked it where I thought the right amount of spring tension was.
If its internal YES just replace! so why are we even talking about fixing it? well at least its covered the procedure for external parts repair in an emergency situation, so all good