Yamaha DT360 carburetor is finally dialed in

Finally got this bike running right. Had to mess with the main jet and needle position a bit, but its running flawlessly now and ready to hit the road!

[@vicjames2743]

Very nice. I had a 72 Yamaha 125 at3 many years ago. Regret giving it to a friend to work on. Love those enduros

[@Garage2Trail]

Thank you! They really are great bikes.

[@robm3357]

That bike looks amazing. Really looks great. I remember all these bikes from my youth. And even back then I was always trying to get them to run properly. Really temperamental to temp. When it comes to two stroke plugs I like to see them a bit on the rich side. As fuel helps cool the engine. Notice how the old 2 stroke bikes always make the wing ding sound and todays bikes run much richer and seldom make the wing ding ding ding unless there very hot My X trainer always sounds to rich unless it’s very hot.

[@Garage2Trail]

Thanks Rob! That’s a good point…about the “wing ding ding” sound I don’t think my Beta does it unless I’m about to run out of fuel lol. I plan on keeping a close eye on the plug and do some more pulls up and down the road just to make sure.

[@redtobertshateshandles]

Half a tank of fuel is a good idea.

[@wattie1050]

Bike looking great there and sounds brilliant ! Glad you have it running sweet , think if you keep an eye on the plug for running too lean should be good to go . That carb design is great for ease of main jet changing saves you dropping the float bowl off all the time .😁👍

[@Garage2Trail]

Thanks my friend! Yes, that carb makes tuning a breeze! Wish they were all like that lol

[@toddjacobs5660]

So at the beginning of yr video you said mid range was kind of running ruff, then you changed yr main jet, now i would have moved my C clip up, dropping my needle to lean it out just a touch, for the simple reason, yr (pilot jet is is for idle to 1/4 throttle) yr (needle & clip is for mid range) & yr (main jet is for wide open) you may know this but i just wanted to throw this out there .. But it sounds like you nailed it over all, sounds like it should 👍my oldest brother had a green DT360 like 45 yrs ago, great ol bikes .And last but not least, keep an eye on yr sparkplug for a true over all reading, sparkplug does’nt lie .

[@Garage2Trail]

Thank you for sharing that! I haven’t had this bike out for a while but plan on keeping a very close eye on that plug. Kinda scary having to lean it out that much but the couple times I’ve checked it it looked good.

[@blackhat400]

Its an 0 ring thats worn on the jet setter, [ not that bit the main jets on] ,its the bit that screws into the bottom of jetsetter /emulsion tube some call it, its located where normal Mikuni main jets screw in, thers an rubber 0 ring on it,[ when worn, fuel passes bye , thats why you have to compensate with smaller jets] once you change it, you"l have to go back to standard jetting, Early Ts250"s are same style carb, See Dale Swager TS250 carb rebuild,

[@Garage2Trail]

I thought that originally because I had the same thing happen on my DT250. New oring there and it persisted unfortunately. I appreciate the help though!

[@gregweeks4980]

So you are thinking that you're needle jet is warm internally. Both of my 74 360's do something very similar. That is a pretty radical jet change, but I am game to try it. I like it that you have done the exploring of Jet changing first Texas on the prairie

[@Garage2Trail]

Yeah that’s what I was thinking. A friend of mine that’s had experience with these bikes seems to think so too. It’s a huge jump down with that jet but the plug and the performance show it’s happy so I’ll just keep an eye on it for a while and check that plug from time to time. I would just do one jet down at a time in your case too and check the plug after every pull. Good luck and keep me posted how it goes for you!

[@lawerncemiller6557]

I've found that using aftermarket jets sizes don't always match up with OEM jets in sizes but going down that many sizes seems a lot be careful not to get to lean 2strokes sound and run good a little to lean but get to hot also on longer rides

[@Garage2Trail]

Thank you Lawrence, I was thinking that since they are aftermarket. I’ll be keeping a close eye on the spark plug condition to make sure I don’t blow a hole in the piston..or worse. I appreciate the input.

[@TheScottiem303]

It’s a mismatch of the needle and OEM seat. Need to be a matching set. The angle of the needle tip and seat have to correspond exactly.

[@Garage2Trail]

I was thinking that because I did have to purchase the needle separate. I was able to confirm the part number and the number printed on the needle itself though is for that carb. Could be the seat like you mentioned as well.

[@daveypenn211]

I was always told to check the plug colour on main jet by riding up an incline on full throttle and kill the engine, stop and whip the plug out. Seems that DTs and TS's are plentiful and cheap in the usa, £1500 for a cheap one here in uk and most of them are imports from usa.

[@Garage2Trail]

Thanks Dave, I’ll have to remember that. I hope to have this bike back out soon as spring is around the corner and the weather should be getting better. There are still a bunch of DTs around still. Haven’t seen as many TS’s in my area though.

[@daveypenn211]

@Garage2Trail Enjoying your channel, it's a good balance between fixing the bikes and riding them. Particularly like seeing them just how they arrived, doing the bare minimum to get it started and then making them look and run nicely

[@Garage2Trail]

@@daveypenn211 awesome! I’m glad you are enjoying and appreciate the feedback. That’s exactly what I was shooting for when I started this. Not looking to make full restoration projects only to be too nice to want to take in the woods and enjoy them.

[@jamesbond-mp3jz]

Make sure your inner spark arrestor is clear.if it's plugged it will make them blubber every time.

[@Garage2Trail]

Thanks for the heads up! I’ll double check that if I have any more of it, but I think I got it figured out with the jetting.

[@HRMayo]

Lowering the clip richens

[@GusMoore-j7r]

Thanks for your Info Brother

[@Garage2Trail]

No problem! Thanks for watching!

[@GusMoore-j7r]

My sister just brought me her 73 360 RT from Colorado to get running. It’s not been used for a long while, the battery actually took a charge and it’s holding, but I noticed there’s no decompression lever or cable on it and something missing (tube or something) on the carb. I’m going to pull the tank and look into the carb, and I just ordered an old used manual for reference… I’m going to try and have them a good little bike by November if I can. They’ve had it over 40years. I’m going to need some pointers for sure, I’ve never worked on one before, but hopefully everything will work out, at least it’s pretty much solid and not messed with by too many monkeys! You might hear from me again. Thanks again Brother

[@Garage2Trail]

@user-rg4ww4fe6c absolutely! If you have any questions feel free to reach out and I’ll try and help out

[@Mark-mq1cc]

yeah something is wrong if a 100 mj is working. That carb is drawing fuel from somewhere it shouldn't. Or it is severely starved of air.

[@Garage2Trail]

Yeah it’s a weird one…the air filter is new and not clogged either.

[@bluestripes1]

my dt360 likes 160 main

[@Garage2Trail]

Good to know, thank you!

[@robertsrbell7811]

I put a after market air filter in mine ran rich real bad that was my problem just saying.

[@Garage2Trail]

Thanks for the input…when I was working on it I think I ran it without a filter up the road real quick to rule that out. I am using an aftermarket UNI filter.

[@usairchairmanpfd2889]

Sweet Ride Mate!

[@Garage2Trail]

Thank you! 🍻

[@jeschreindl]

That plug looked perfect

[@Garage2Trail]

Thanks Josh. Good to have more confirmation on that!

[@jeschreindl]

I bought some of that permatex assembly lube that you have for at home and my work. I like it alot better than the royal purple we normally use. It’s a lot tackier and odorless

[@Garage2Trail]

@@jeschreindl that was the first time I used the stuff…I was surprised with how tacky it was. Like honey lol

[@redtobertshateshandles]

Old two strokes need crank seals replacing. After 50 years those neoprene seals are long gone. That's why I'd like an XL350 Honda.

[@Garage2Trail]

I’ve had to do a couple crank seals…the MT250 requires the engine to be split but the Yamahas are easier if you can just pull them out. Still gotta get behind the clutch and flywheel though. This DT360 didn’t need them done thankfully. I have a 74 XL350 as well! Very trouble free…just gotta make sure the cam chain tensioner works!

[@rogerbrewster8]

Awesome man. I'm having the same trouble with my 72 Dt250. Might try the same stock calls for 150 or 60

[@Garage2Trail]

Also, before you change jets have a look at the small oring that’s on the bottom of the needle jet that sits down into the bowl. My 75 DT250 had a worn one and it caused the same problem.

[@JEMadaras]

Hell yeah

[@johnnynewburgh9745]

Hey Garage went through jetting issues as well with RD 350. Looks like stock pipe do you have stock air filter? Anytime you change air flow or exhaust you have to re jett carburetor . Double check your specs make sure 180 main is what it called for. On my bike had to get K&N air filter could not find stock one. All the info I read said go with 140 main if using k&n in stock box. Tryed that but way to Rich would rev over 5k. That recommendation of 140 main was if you had 120 main original. My bike came with 105 main jet so going up 3.5 size way too big. Do not know if 120 different year European model etc. At 115 main now 2 sizes up going good

[@Garage2Trail]

Good call Johnny…it is running the stock pipe and air filter. The manual specs do show it as a 180 but who knows what was it it when I got it. I couldn’t read the markings on the jet it was so worn away. With it being 50 years old and probably worn out brass in that needle seat…I’m sure it throws things out of whack pretty good!

[@johnnynewburgh9745]

Are you familiar with the marking's on Mikuni jets the little square with notch in it and a dot? I think a lot of after market jets not marked clearly or at all. Also magnifying glass may be useful

[@Garage2Trail]

@@johnnynewburgh9745 I was unaware of square with the notch symbols on them but will need to take a look. I didnt see that on the jet I removed that came with the bike so its very possible that could be aftermarket and the wrong one. The kit I got is definitely aftermarket. Thanks for the heads up!

[@ramishrambarran3998]

T

[@Garage2Trail]

I did replace the needle with an NOS one I found online. I’m thinking the brass needle seat may be worn which caused it to compensate with such a lean main jet

[@ramishrambarran3998]

@@Garage2Trail I understand. This was a condition you'd find in the days of the old English cars that used Stromberg Constant Velocity carburettors. (Of course in the late 70s the Japanese started using. CV carburettors also.) Worn needles were common. Regards. Trinidad & Tobago. West Indies.

[@Garage2Trail]

@ramishrambarran3998 thank you for the tip! I appreciate it

[@ramishrambarran3998]

@@Garage2Trail Hi. I meant that in the late 70s the Japanese MOTORCYCLE manufacturers started using CV carbs !

[@novaguy383]

On all of my old bikes the needle jet was worn. The hole was way bigger than when new due to the needle wearing the hole bigger over several decades of use. A new needle jet cleaned up part throttle running nicely.

[@Garage2Trail]

I’ve experience the same thing on my 74 XL350. Worn out and running rich on the leanest clip position. Runs good though. This 360 has a brand new needle but the needle tube I believe is really worn out.

[@bananabrooks3836]

​@@Garage2TrailYes, 100 main is a heck of a drop from 180 stock so the carb is passing more fuel from somewhere, new needle and needle jet may prove the theory.

[@Garage2Trail]

@@bananabrooks3836 I do have a new needle in there and confirmed it’s the correct one for that bike. I’m starting to think maybe that carb is off another model.

[@rippn6124]

Slide, washer under jet, emulsion tube/ holes, needle/ taper... Down 20 just to tell " if..." Sir, now 140, Needle position wasn't stock... And your rejetting AGAIN. 190 TO EYEBALL'N .000! Learn what circut controls what rpm. The Manuel says 180...something is wrong w/ YOUR MISUNDER STANDING. YOUR RUNNING ON VIRTUALY NO MAIN JET. Learn to CHOP/ READ a plug. CORRECTLY! 100 MAIN/-80 SMALLER! KABOOM! ..."spot on" Bwhahahaha!😂 Learn the REAL Names of things. Read a plug on the ring at the base of the insulater. "One step at a time" ... try it.

[@rippn6124]

Was 100 stock main in Manual? I see a stock Smuffler, but hear dif. Jetting substantiated? Slide cutaway, idle speed, needle, centered in emulsion tube. Old slide rattle? What airbox mods? Had throttle hang? Manifold, old stock? Test it/ manifold seals. Stretch the slide spring? trying to "fix" a problem undiagnosed? New grips? Clutch lever askew belies You aren't methodical. Check spokes, whl bearings, shocks junk? 50 yr+ brake shoes? Inspect/ lube shoe Pivots and shaft... Both wheels... Change fork fluid... Fork Seals... Un ethanol gas?😁 Tank/ petcock clean? 17% LOSS W/ dry chain... I'm nobody... Happy to think!😁

[@paulthompson8613]

Sounds sweet

[@Garage2Trail]

Thanks Paul!