YZ-80 (1985 Model) Replacing Piston and Connecting rod with Chinese

Master Hack

Master Hack

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On line parts fiche is your friend.

yamaha

PISTON 1 O/S 0.25

PISTON 1 O/S 0.25
58T-11635-01-00

$82.70 x 1 = $82.70X

ROD,CONNECTING

ROD,CONNECTING
39K-11651-00-00

$77.43 x 1 = $77.43X
 
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panchothedog

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If you can find one, a parts bike is not a bad idea. At pushing almost 40 years old, they might be far and few between. Almost old enough to be in restored motorcycle territory. If you can't afford a rod and piston, how do you think that you will get a new engine. Maybe a less expensive hobby until your financial situation improves.
 
Jacka$$withawrench

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panchothedog said:
If you can find one, a parts bike is not a bad idea. At pushing almost 40 years old, they might be far and few between. Almost old enough to be in restored motorcycle territory. If you can't afford a rod and piston, how do you think that you will get a new engine. Maybe a less expensive hobby until your financial situation improves.
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If I can find a parts bike, maybe. I can press the bottom apart (I built a press) but to get the rod is a trick and a half.
 
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The one thing I fell in love with on the 1970 Honda SL175-K0 I had was the fact like it's sister bikes (CB175, CL175) and probably a few dozen others was that the case was split horizontally Not vertically down the middle.

I've worked on a lot of bikes over the years, and never needed a press for anything; that includes splitting, reassembling, and truing cranks... brute force used with the right precautions always gets it done for me well enough.
 
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Rat said:
The one thing I fell in love with on the 1970 Honda SL175-K0 I had was the fact like it's sister bikes (CB175, CL175) and probably a few dozen others was that the case was split horizontally Not vertically down the middle.

I've worked on a lot of bikes over the years, and never needed a press for anything; that includes splitting, reassembling, and truing cranks... brute force used with the right precautions always gets it done for me well enough.
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Are there sister bikes for an older gen yz? Will a 95-yz80 rod fit a 86 yz-80 engine? If not, is there a site like Engine, Transmission, Chassis Swap Donor Vehicle Look-Up (roadkillcustoms.com) for donor bike lookup?

probably cheaper to just get a new motor
 
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Jacka$$withawrench said:
Are there sister bikes for an older gen yz? Will a 95-yz80 rod fit a 86 yz-80 engine? If not, is there a site like Engine, Transmission, Chassis Swap Donor Vehicle Look-Up (roadkillcustoms.com) for donor bike lookup?

probably cheaper to just get a new motor
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For the most part a YZ, is a Yz they didn't change much more than the plastic from 88-01. Beyond that I can't say much for the Yz.
I bike with that many years production tend not to have siblings unlike the Honda SL175 which was only made for 3 years starting in 1970, However just about any 80-90cc 2 stroke should slide right in and bolt up nicely, but it won't be cheaper than a $300 genuine rod/piston kit, nor will it be cheaper than some generic chinese crap, unless you find someone's used, abused, and outgrown junker to cannibalize and you'll still need to get new piston rings.
 
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Jacka$$withawrench

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Rat said:
For the most part a YZ, is a Yz they didn't change much more than the plastic from 88-01. Beyond that I can't say much for the Yz.
I bike with that many years production tend not to have siblings unlike the Honda SL175 which was only made for 3 years starting in 1970, However just about any 80-90cc 2 stroke should slide right in and bolt up nicely, but it won't be cheaper than a $300 genuine rod/piston kit, nor will it be cheaper than some generic chinese crap, unless you find someone's used, abused, and outgrown junker to cannibalize and you'll still need to get new piston rings.
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Would an electric motor solve any of these problems? I could mount a motor to the cylinder bolts and run a chain to the clutch from there, then stick batteries and a controller above it.
 
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Jacka$$withawrench said:
Would an electric motor solve any of these problems? I could mount a motor to the cylinder bolts and run a chain to the clutch from there, then stick batteries and a controller above it.
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No it wouldn't. Setting up for Electric is also easily 4x more expensive than gas, a good quality controller that could handle enough power to be worth using would cost around 1200 probably for a cheap less than fun one
 
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Jacka$$withawrench

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Rat said:
No it wouldn't. Setting up for Electric is also easily 4x more expensive than gas, a good quality controller that could handle enough power to be worth using would cost around 1200 probably for a cheap less than fun one
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couldn't I just throw an adjustable resistor to it and call it a day?
 
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I've done some digging, a full rebuild kit for a Yz80 (crank, rod, piston, rings, all gaskets, all o'rings) runs around 280-350 on ebay.

That's about the cheapest you're going to get.

Replacing the engine outright with a parts bike, might cost more in other needed repairs.

Replacing the engine with new, will definitely cost way more, and you won't get a 2cycle so you may as well go bigger (110-200cc)

Doing any degree of electrical conversion will cost the most.

Do it right or not at all
 
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65ShelbyClone said:
What I'm wondering is why the connecting rod is missing in the first place.
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Well first off it's a solid rod like a lot of Motorcycle engines, which means they are sandwiched between press fit crank balancers, the automatic suspicion is the conrod exploded.

One does NOT remove a solid conrod from a spit crank without removing and disassembling the engine... but it can remove itself if it so chooses and it is not uncommon to take the top end out when it let's go.
 
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65ShelbyClone said:
That's why I was wondering.
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Because the engine in question is 2cycle, it only takes one f★cktard to run it without premix oil, or one dip★hit overreving it too hard for too long (trying to do 50 in 1st gear) combine the two errors and even a brand new 2cycle engine will frag out in short order
 
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