Vernjeggies

Spent yesterday tearing the engine down. The PO told me he "rebuilt the engine" before he traded it to me, but after he also said he "took all the best condition parts from the three engines and put them into that one" I knew I needed to check. Good thing I did. Re-used rings and gaskets, changed out the cylinder without even a hone, heavily greased the connecting rod bearing, and a seized oil pump. This project is something else . Then, to add insult to injury, I took the frame to my brother today to have him press out the swing arm bolt. He did a rushed job and somehow cracked the top tab in two places. Didn't even push the bolt all the way out. Turns out he was late getting to the gym... still need to get the bolt out completely to really assess, but I might be doing some fabricating and welding of a new tab in the near future. Most of the shiny spots are just removed paint with no actual damage, but the cracks are concerning. Lesson learned. If there's a next time, take it to the professionals. It'll be worth every penny.

I think tonight I'm going to try laying the frame down on the floor, support it from the under side, then trying the WD40 and a hammer again. If that doesn't work, I have a friend with a press that I might ask for a favour.

Oh boy... I'm really looking forward to that now haha

Yikes! I'm a little uneasy about getting an angle grinder anywhere near there. There isn't enough room for the blade between the frame and swingarm

Over the last couple days I got into it hard. I decided I'm going to sand blast the frame and re paint it, so I started the tear down. Got the engine out and the bulk of the rear end stripped down. I'm at a stand still now though, because I'm having a serious problem getting the swing arm pivot pin out. Its seized pretty bad and it takes almost all of my 190lbs standing on the ratchet to even turn it. The nut came off easy enough, but so far heat, WD40, and hammering wont budge it. The swing arm wont even drop under its own weight... Anyone have experience with this at all?

A little bit of back story: I traded a blown up 92 RM125 to a guy for, what he said was a complete, 1979 DT175 with no papers. Had a look over everything and although the ignition wasn't assembled, it looked all there. Came with two "parts motors" so what the hell, right? After having it in my garage for a couple weeks while I finished up a couple repairs on my other ride, I finally got to actually dig through the parts box and run some VIN numbers to see what I had. Turns out the bike is a 78 and the engine numbers match! Also, turns out its got everything to make a complete bike. Catch is, its all for 3 different years. Closest I can figure is, he had the 78 and something happened to the ignition. He found a 76 and stripped off the wiring harness and a few other parts, and converted the 78 to points ignition, discarding the original set up completely. At some later time, the points cooked, and he found the engine from an 80. When he realized that The CDI ignition from the 80 didn't plug directly into the 76 harness, he flogged the whole bike into my open arms haha. Needless to say, its a wiring nightmare. Ive decided to buy a used complete harness and ignition set up and re set it back to 78 electrical. Then I decided, "why stop there?" My first restoration project was born.

Yambits is the best site so far! Thanks for the directions

Finally got my Clymer manual. Look like I'm going to be a frequent eBay.ca customer haha. I checked all of the references that you guys gave and found some stuff, but eBay seems to be the way to go for most of it. There are a couple really good scrap yards in my area that I have yet to wander through as well. Thanks for the help everyone! Might have to make a project thread for this one. It will be my first restoration.

I guess as long as it's from a year that had monoshock. I'm not too worried about original right now. I was even thinking of re jetting and running a pod filter and capping the oil pump to run mixed gas just to get it running, until I come across original. Thanks! Partszilla doesn't have a lot since most of the big stuff has been discontinued and is unavailable now. I'll have a look at the rest of these though. Thanks a lot

Thanks anyway... I used to use 4into1.com for my Honda stuff, and regulatorrectifier.com for electrical, but neither has anything for this year of Yamaha

I'm going to need a wiring harness, CDI, Stator, flywheel, oil tank, piston rings, gasket kit, air filter, maybe and air box

Haha I would've had a heck of a time trying to figure out why things weren't working out! Now.... any ideas where a guys finds things like electrical parts for a bike from 1978? I found some stuff on eBay, but I'd rather find a reliable resource for online parts, since I'm going to need a few other things. Any suggestions? Seems like parts for the 78 and earlier are almost completely unavailable.

There is! Thanks for pointing that out. It never would've occurred to me, but the harness is actually off the 76...pre CDI.

Hopefully my clymer manual shows up soon. I'm not sure what out of this box of parts even goes on this bike anymore. Haha Both frame and engine numbers start with 2A7 however I have parts motors with 559 and 3V5 prefixes. From what I can find, the one in the bike is stock and a 78. The parts motors are 76 and 80.

So I finally found a wiring diagram on google, but none of the components are labelled. It looks like the CDI and stator that I have are definitely not for this bike. Potentially for a 79? Anyway, I guess that puts me in the terrible position of looking for electrical parts for this old machine. Any suggestions? Also, it looks like this diagram shows what could be a battery (#9)? I didn't know it had one. My wiring harness definitely doesn't have any battery connections.

The biggest problem I'm having is that I don't even know where the stator would plug in to. There's a random red wire off my wiring harness, but it's not grouped with anything. The stator that goes with the CDI doesn't have a red wire, no.

Nice! I'll keep that in mind

Wow Airhead that's amazing information! I knew there were some knowledgable people on here but that was next level. I have the 175E... does that fit in to either of those categories? It's got the round swing arm. Unfortunately, not only am I working with a box of random parts, half of the connectors have been amputated. The stator I'm working with is a 5 wire with no connector and the CDI is a 6 wire with no connector and no red wire. I'm starting to think these parts not belong on this wiring harness?

Thanks guys! Finding lots on the 79 in here but not many 78s by the looks of it. Can't wait to get my manual in the mail so I can get this thing running haha. Good thing theres a couple feet of snow on the ground or I'd be going nuts.

It seems like it was originally a CDI. Everything is there, just need to figure out what colour wire goes where! Anyone holding an electrical diagram?

Yeah it's a monoshock. I don't know why the PO would have switched it to points.... doesn't make much sense to me

Hey everyone, Just picked up this bike and I'm eager to get it running. PO did an engine swap and now the numbers match, but he attempted to change the ignition from CDI-> points... or maybe vice-versa. I have a Clymer manual on the way, but I'm curious if anyone on here has an electrical diagram for this year or at least knows if the 78 was CDI or points? The bike came with a parts box containing both... Any help would be awesome! Thanks in advance

Hey everyone, I just got my second Yamaha enduro, and I know from previous experience building my first bike (a Honda cb650) that forums are a crucial source of experience when trying to nail down certain things that might not be specific enough to be covered in a manual, or too old to find parts for. I picked up an 82 XT200 a few months ago. No papers, but it holds up well off road... well enough for my needs anyway haha. Then, a week ago, I had an opportunity to trade off a blown up Suzuki for a 1978 DT175, almost complete with 2 parts motors. Needless to say, I made the trade! Now here I am. Looking forward to learning lots, and contributing where I can! Cheers