RZ350 fz swingarm dog bone cut & weld vs make new?

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Speedfreak955
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RZ350 fz swingarm dog bone cut & weld vs make new?

#1 Post by Speedfreak955 » Sat Aug 23, 2014 10:35 am

Hello all,
I've been poring over all the threads about this subject and I need a little help please.
My local welding shop said he would not cut and weld my links. Does anyone in Georgia know where I can get this done?
The other option is to make a set the proper length. The suggestion has been made for 4140 5/8 x 1 1/2 and thread in the old rz shafts after cutting them.
Then send this to be heat treated.
These units appear to have been grossly over built to start with.
Please any advice or links to other threads on the subject would be greatly appreciated.
Speed

hondaror
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#2 Post by hondaror » Sun Aug 24, 2014 2:43 am

Your local welding shop is smart. Those links should not be cut, welded and reused.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

Speedfreak955
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#3 Post by Speedfreak955 » Fri Aug 29, 2014 6:25 pm

New links made.
:smt003
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alan1949
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#4 Post by alan1949 » Fri Aug 29, 2014 7:57 pm

I've repaired/ reclaimed many things in heavy industry for the past 45 years using many different forms of welding for a variety of materials and their different grades. The bottom line is if its done properly there will be no problems. Welding uses science and technology not black magic but having said that have it done by a professional. Although certain metals are not weldable the rear suspension links should not present a problem and this mod has been done successfully many times before. Anyone with positive or negetive experience making this modification please comment.

hondaror
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#5 Post by hondaror » Fri Aug 29, 2014 8:57 pm

The bike looks really good. I'd prefer a silver swing arm.

Are the wheels Dymag? ...or FZ?
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

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aaronmvrider
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#6 Post by aaronmvrider » Fri Aug 29, 2014 11:28 pm

how does the chain clearance look at swinger pivot area...

running a larger 17 or 18 tooth front sprocket might help clearance and obviously a smaller rear sprocket for ratio..
1 x 4mm stroker rz 375cc 1983
1 x 7mm stroker rz 443cc 1984 (under construction)
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Speedfreak955
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#7 Post by Speedfreak955 » Sat Aug 30, 2014 7:39 am

hondaror wrote:The bike looks really good. I'd prefer a silver swing arm.

Are the wheels Dymag? ...or FZ?
Wheels are Fzr front and SV650 rear. I figured the swing arm would be more of a classic look in black.
Besides :smt003 I wasn't gonna polish it :smt003

hondaror
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#8 Post by hondaror » Sat Aug 30, 2014 12:53 pm

I wouldn't polish it either.
Rory
2 1984 RZ350s
1985 RZ350
9 1986-1990 RZ350s
2000 ST2
2005 749
2005 749 with 999 engine

mkane
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#9 Post by mkane » Sat Aug 30, 2014 7:12 pm

If there's issues of chain rub on the swinging arm run a simple chain tension devise. Problem solved.

tobster
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#10 Post by tobster » Mon Sep 01, 2014 12:17 pm

I've had my dogbones cut and welded by a guy who is a welder at Williams F1. He has rejected other parts to weld, but he was very happy to weld them, and did a beautiful job.

RZtuner
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#11 Post by RZtuner » Sat Dec 13, 2014 7:02 pm

Do a spark test on the dog bones and you will find they are made of high carbon tool steel. You need to TIG weld with a special HC filler rod. I did a set and welded a sacrificial spare. Couldn't break the weld with a 5 lb. sledge hammer. Super tough. Yes they can be welded, but do it right. Easy for somebody who has no concept of metallurgy to do it wrong.
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mountaincycle
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#12 Post by mountaincycle » Sun Dec 14, 2014 10:28 am

Nice bike Speedfreak955.. :smt023
I'm in G'ville, S.C. What part of Georgia are you located?

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ricar
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Re: RZ350 fz swingarm dog bone cut & weld vs make new?

#13 Post by ricar » Sun Dec 14, 2014 4:54 pm

Top secret... They are cast steel not cast iron. Very easy to cut and weld. Did mine last year.
84 RZ. Half naked, SpecIIs, GSXR front end, FZ swingarm, SV rear wheel, trail tech speedo/tach

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