Differance between a 69 TC120 and the TC120-II engine parts

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gr120
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Suzuki 2-Strokes: 1964 650 Triumph,1969 S TC120,06 750 Honda

Differance between a 69 TC120 and the TC120-II engine parts

Post by gr120 »

I have been getting "bricked" in getting the correct engine part numbers for my TC120-II (1969 Suzuki). I was told the problem may lie in the -II. Truthfully I have never know what the difference in the two models are. There are people listing piston and rings for sale and they are listing the SAME part numbers for standard and over-sized. It's are real kick in the pants because they don't seem to know what they are really selling and I am not positive of what I should be buying. I have tried dealers and and forums to come up with the correct part numbers for my machine with no luck. I did find a parts book but I would have to invest $60.00 to obtain a number for a part that in the end is no longer available. Hate to go that route but I am getting close........ Anyone out there that can bail me out would be greatly appreciated, I am trying to get it running for my grand children, I logged a lot of miles on this machine as well as their father, and would love to see 3rd generations of riders.................

I am after the piston and rings for standard or1 over (5.0) or 2 over sized (1.0) I would bore the cyl to whatever I could find.

Thanking you in advance,

GR
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Alan H
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by Alan H »

Get a genuine suzuki parts catalogue and then you'll know.

ebay number 111715469069 these give 'exploded' views of ALL parts of the bikes for all years if you get the later versions. Suzuki do this for all models and the books are invaluable.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
GT750Battleship
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by GT750Battleship »

Hi GR,Alpha Sports Suzuki list these part numbers for the TC120 mark 2, 1970
Standard Pistons:12110-20021
First Oversize 0.5: 12110-20720
Second Oversize 1.00 12110-20730

Standard Piston Rings: 12140-20211
First Oversize Rings: 12140-20721
Second Oversize Rings: 12140-20731

Alpha Sports Suzuki do not have a listing for 1969 models, Also be aware there could be supersession of part numbers after all these years.... :shock:
Regards,
Roger
Suzuki GT750A
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gr120
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Joined: Tue Jul 21, 2015 6:05 pm
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Suzuki 2-Strokes: 1964 650 Triumph,1969 S TC120,06 750 Honda

Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by gr120 »

Thanks Rodger,

Really appreciate the feed back and possible numbers for the 69. The "Bike Shop" that has my cylinder call me this morning and he figures I will need the 1st over size piston and ring set after the boring takes place. He has checked with all his suppliers and he cannot find any of the parts to rebuild. I gave him the part numbers for the 0.5 that you supplied me and was unable to get a nibble. So he put the bore on hold until I try to come up with the parts.

You are absolutely right about the possibility of updated part numbers. I had two of the largest Suzuki dealers in the Tri State Area (PA, NJ, and Delaware) tell me that they had no way to cross reference the numbers period. When I struck out with the Corporate Center for Suzuki in Calif I knew this was going to be all "up hill".

Boils down to I "think" I need the 12110-20720 with the 12140-20721 Ring Set or whatever upgraded numbers that may have transpired. I am assuming that the 69 and 70 parts are interchangeable. At least that is the feed back that I am getting. The confirmation of the parts listed for sale are really what they claim they are is a major hurtle that I have been warned about by a guy who restored a similar "Bike" to mine. Would be easier to just let the Grand Kids ride my ATV than to fire the "ole girl up" but I still would love to hit that 3rd generation ride.

Thanks again,

All the best,

Gus
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by GT750Battleship »

:) Hi Gus,part number 12110-20720 also used on,
1965 thru to 1967 Suzuki B100,B105P,KT120 models also on the TC120R Cat ?
If any of this will help you source something ! as you say it would be nice to see it live again & be enjoyed by the young ones,lots of luck :up: PS have you tried getting in touch with your local VJMC Club,might get some more info from them,just a thought !
Cheers,
Roger
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jeff g
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by jeff g »

According to my parts catalog for the TC120, TC120-II, and TC120R, all 3 use the same piston and rings. I have to go to my storage unit today, so I'll look and see if I have what you need in my pile 'o parts which includes several hundred pistons and rings.
jeff g
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by jeff g »

One thing to watch for about NOS Suzuki pistons and rings. Suzuki used 3 different styles of rings over the years and they MUST be matched to the appropriate piston. They used thick rings, thin rings and keystone rings, and they were matched to piston styles. Obviously, they may not have used all 3 styles on all bikes, but things did change over the years. Many dealers re-marked boxes when the supercedes came in, so it's easy to get a piston of one style and the rings for another style. You have to go by either the original numbers on the box (if available) or by physically matching the rings to the piston. All of the ring styles are visually different and the differences are pretty obvious. When I pull a set of pistons and rings out of my pile 'o stuff, I physically match them up to make sure that I have matching parts.

Jeff
jeff g
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by jeff g »

Gus, check your PM and email. I have your pistons and rings.

Jeff
GT750Battleship
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by GT750Battleship »

:up: well done Jeff,let's hope the gentlemen is still reading this forum...& his PM's !
Cheers,
Roger
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jeff g
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Re: Differance between a 69 TC120 and the TC120-II engine pa

Post by jeff g »

A day late and a dollar short...Gus found his parts a couple of days before I saw this thread. Oh well, eBay I guess.
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