Trevor's Triumph

I’m kinda pissed at the Fiero for spinning a rod bearing. In lieu of that, I decided to throw a bunch of money at the 1973 Bonneville 750 I picked up about a year ago. I’m going to be placing a Cognito order fairly soon to get my custom wheelset and triples for the '08 GSX-R 1000 front end I’m putting on. I have a seat on the way along with a bunch of other parts. Of course, an assembled picture:

…and then I pulled the Unit assembly out and lopped the back half of the frame off. Still need to cap the lower tubes with some flat plate and quality TIG time.

Threw the swingarm in there to get an idea of how things are going to work. I’m swapping the greased bronze pivot bushings for needle bearings. I’m going to powder coat the swingarm black.

I was liking it, so I throw the fork in just for a real rough mockup. I got a steering stabilizer with the fork. I might use it.

Ideally, I’m trying to maintain tank positioning similar to factory and maybe a slightly lower ride height. I need to get my wheelset ordered and built with the fork properly mounted so that I can measure and make the appropriate rear wheel and swingarm spacers to maintain chainline. This will also give me the opportunity to measure, order and mount my rear shock (hopefully a Penske). That will allow me to make a seat hoop and mount the seat; then mount the rearsets. I’m really hoping to be done in a handful of weeks. We’ll see. Motor doesn’t need much. It ran okay, just smoked a bunch. It’s a fresh .040" over rebuild with new parts. I have all of the receipts for it. I think the rings are stuck from sitting for a few years after the rebuild. I’m hoping. I’m going to pull the jugs off while I’ve got the motor out and see what I see. I thought about ordering one of the LowBrow motor stands. I kind of want to mount it to a Lazy Suzan. Should make my life easy. Fucker’s HEAVY. Anyway, I’ll keep working on this. This is kind of what I’m trying to do. Kind of.

Cognito is pricey but makes some high quality parts for the most part. I’m running his complete retro triple setup, seat pan tray, rear-set adapters, etc. This time around I purchased the complete hub adapter he makes for the GSXR front wheel setup as I want to switch my wheels around a bit. I’m also running that same MotoLanna seat shown in the last picture. Looks like someone re-wrapped it as I did the same with mine. The material that comes on it is pretty crappy but it’s expected for the price/location of manufacturer of the unit. I’d also highly recommend a steering stabilizer as you suggested.

Looks good so far! Stoked to see more people on here into motorcycles. :tup:

Awesome that you started to work on the T-140, fuck cars. Pull the barrels and investigate, I had Jr “help” me and it took about an hour, including him running away with tools I needed. Never know, the previous owner may have squirted some oil down the plug holes thinking it might be sitting for a bit.

A few things showed up, so I slapped them together. I think I’m going to work on the motor while I wait for wheel parts. Still need to wait a few weeks for funds to order them. Starting to look kinda nice.

whoa. :bigtup:

I can dig it.

I worked on this a bunch today. First, I made a motor stand instead of spending $60 on the one from LowBrow. Works great and it was free. I’m happy with it.

Anyway, I got the stand mounted to my little plywood table and then I threw the motor on it. Made taking all of the covers off much easier. So. Much. RTV.

I wanted to check the state of things like the stator/rotor, clutch components and oil pump. Not sure about the stator/rotor, but everything else is shot. Oil pump seems like it works, but I’ll guarantee it’s original and I don’t trust it, so it’s getting replaced. I’m also adding an external screw-on filter to the pressure side of the scavenge stage for funsies. Clean oil is happy oil.

I bought a Deutsch crimper so I can use those connectors everywhere and I’m going to use braided cloth primary wire to build the harness. I also bought a battery eliminator regulator [capacitor] that I’m going to mount low on the front of the frame in the wind for cooling.

Placing a large order with Classic British Spares tonight or tomorrow for that shit and some more. They’re running a Black Friday/Cyber Monday special; 10% off of everything.

Stay tuned for more. I’m ordering a rear Ohlins shock from a Daytona 675R, wheel parts and triple trees in the next week or two.

So much clutch wear… Christ

PLENTY of life left in that clutch… Dude, who did the rebuild on that?

I’m not really sure who did that type of work on it. Klispie did the actual motor work, but I don’t know how much they disassembled/reassembled. I have receipts from them for four valve guides, two valve seats, a valve job and a bore and hone to the tune of $500+. None of the important shit was replaced, but I’m sure that has more to do with Lou being a cheap fuck than Klispie being a shitty machine shop. There’s what looks like the original oil pump and original clutch components which are bad enough 40 years later. I’m trying to head over there tomorrow and pull the jug. We’ll see what I find. I’m hoping to just be able to clean the fuck out of the ring lands and replace them with the new ones I ordered. The more I take this motor apart, the more shoddy work I find.

Pulled the cylinder head and jug today. Found a bunch more stupid shit.

Like this non-matching hardware:

…and these stretched head bolts:

None of the head fasteners had any real torque on them. One of those head bolts even had oil all over the threads. I’ll bet that explains my oil problem and it running like shit. Rings look fine. Piston skirts are kinda scuffed, though. Normal for a motor with roughly zero miles?

One of the pushrods has loose end caps as well. It’s almost like nobody actually gave a fuck when they ‘rebuilt’ this thing.

Oh, and all of the RTV in the world. I’ve probably spent at least two full hours picking, scraping and wiping all of the RTV away. It’s everywhere.

Hopefully start reassembling the motor next week, if everything checks out.

I really hope it’s your old ass oil pump and not a plugged sludge trap that caused the skirts to look scuffed like that. Jr was asking on the way home if we were buying that motorcycle as that’s what he’s accustomed to doing when we go looking at a motorcycle.

Edit-Maybe, MAYBE, he just fired it up before making sure the pump was circulating oil by opening the oil fill cap in the frame and watching the return when kicking it over??? If you need to take it to the sludge trap, there is a dude on Youtube that does a pretty thorough job, search Lunmad.

Hah! That’s funny. He’s a cute kid.

I’m kinda hoping something like that. I just can’t shake being convinced that with all of the half-assery I’ve found so far, there will be more. …and I have no reason to believe that the crank has ever been pulled and disassembled. If I learned anything from that God forsaken Northstar in the Fiero, if I want this thing to work; I need to tear it down all the way, measure everything twice and replace anything that’s even remotely questionable. I think maybe I’ll spend a couple of days next week splitting the crankcase and QC’ing all of the parts that come out. It’s quite a bit of extra work, but unless I find an imminent failure or something; shouldn’t cost me a whole bunch extra. I already have a complete seal kit on the way.

I managed to find that dude’s videos a few weeks ago. He and the workshop manual helped me get as far with the disassembly as I have. I’m stuck at work all night with not much to do, so I’ll definitely be sifting through his bottom end videos.

So I decided a few weeks ago to tear this down completely to the sludge trap in order to be absolutely sure about this motor. I’m glad I did, but it turn out that Lou’s buddy Kit definitely beat me there. Even scrawled his name into the interior of the crankcase.

…but I polished that out, 'cause that’s pretty dumb.

Anyway, I had to make a buncha’ tools to facilitate getting this far, like a clutch hub wrench and a puller for the primary sprocket and cam gears.

Instead of wasting money buying, or time making a puller; I ended up just heating the crankshaft pinion and prying it off with a tiny prybar, finally wiggling it off with slip-joint pliers. Worked perfectly. The timing side bearing was tight as shit so I heated that and ended up destroying a sacrificial 5.8 spark plug socket while pounding the fuck out of it. I’ll be replacing every single bearing and bushing anyway.

The whole reason I tore it down this far was to check the sludge tube, which I was sure was full of crud. It wasn’t. Apparently that was on their list. Well, I guess that’s good.

Clear evidence somebody’s been in here:

…and a nice clean sludge tube.

So, next time I’m over there I’ll be removing all of the bushings and bearings so that I can soak/degrease the cases. They’re pretty dirty.

I also happened to notice how hammered the front drive sprocket is when I pulled it off. All worn where the sideplates ride and pitted at the pin pivots.

Anyway, I decided to swap to a 520 chain so that I can run an 0- or X-Ring chain in the same space as a standard 530 because a sealed 530 chain doesn’t fit the Triumph Unit cases. This requires facing off some of the sprocket. I decided to practice with my clapped out sprocket before tearing up a new one.

No finished product picture. Seems to have worked. Would just need some quality time with a file and sandpaper to finish it off.

Oh, and check these amazing petcocks. Hand made in Rochester, I’m pretty sure.

Order a bunch more parts and start reassembling the motor/transmission. Stay tuned.

More info on petcocks…

The source of them seems to be this company; based in Rochester. The street view of the company address is a tiny house though, so I’m not totally sure if they make them. Anyway, go to that website, click ‘Custom Parts’ and scroll all the way to the bottom. I actually got mine from The Bonneville Shop. Here. I only paid $118 for the pair.

I’m so full of What the Fuck from this bike? Who takes it down to the sludge trap but reuses that shit sprocket and clutch??? Well, now you know as you split the cases instead of having this nagging question in the back of your mind.

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Holy fucking small world!!! Jim is a good dude. My old man bought his 71 Commando from him back in 97-ish I want to say. And yes, it is his house and in the back he has a garage, like a 2 car garage that houses the goods.

Hah, yea. I don’t understand their methodology on this ‘rebuild’. They reused everything down to the overtorqued, stretched bolts and studs and garbage clutch components. No new bushings anywhere, no new bearings. Doesn’t seem like he even desgreased the cases. Frankly, I wish they hadn’t even bothered. My plan now is to replace everything. Bearings, bolts, studs, bushings. Everything. Probably have the crank dynamically balanced while it’s out. I should also think about Magnafluxing and Ferretic Nitrocarburization as well, apparently. Seems to be recommended for these old twins.

That’s funny. I wouldn’t have suspected that you knew him. Hah. I’d love a Commando. Those are awesome looking bikes. I’d totally consider buying a new one, if they weren’t $20,000+.

Walk around the corner and I might know of one for sale

Lemme finish one or both of these things before I try to start another. Funds for projects. Funds for projects. Hah.

Anyway, I ordered one of these this morning along with some 7/32" water quench drill rod which I’ll use to make brand new hardened clutch pushrods. I got 36" of rod for $9. I believe the factory rod is around 11.8", so I should be able to make three out of that one drill rod. That’s only ~$3 apiece. Kibblewhite sells the same thing for $20+. Damn. Just need to round the ends, torch them red hot and swirl around in a bucket or water. The slave is coming from England, so it should be here in a few weeks. I asked the sales bloke what the piston diameter is and he claimed it’s 23.86mm or .930". He said they use a 13mm Magura master. Perfect.

I’ve found most of the bushings, bolt kits and seals and bearings I’ll need at TheBonnevilleShop. Their prices seem pretty fair after the 10% off. Most of the large bearings are coming from England though, like the main bearings and gearbox output roller bearing. Pretty much everything but the crankshaft and cases are going to be brand new and they’ll be sparkly clean. Gonna have to pretty this thing up on the outside to match the inside, for sure. I should whittle up the required drifts on the lathe while I’m waiting and look into at least a small HF benchtop press. I’ve been looking for a used electric oven that I can use for powdercoating, too. It would actually come in really handy for heating the cases for bearing installation and even removal.