Acquired old Tri moto 125

[jeffwilson0]

My father in law had a tri moto 125 in his shed that he bought new, he can't remember when, he thinks in between 77-79. As long as I've known him (10 years) it hasn't left the shed and he said he was going to throw it out so I offered to take it off his hands, so it's mine now. He does not have the registration for it so he doesn't know what year he bought it in for sure.

It started 2nd pull so off we went, made it about 5 kms and it died when we stopped, and wouldn't go again. So we pulled it with another bike and away it went, then it stalled again, so we pulled it, and this time the chain snapped. Here come the questions.

I assume the carb is pretty gummed up by now, that's no problem to repair, but other than the motor oil, what other kind of maintenance should be done? I notice it looks to be oil injected? What kind of oil goes in that tank? Does anyone know what size chain I need? Here are a couple of pics to help you guys if you can figure out what year.

http://images.cardomain.com/member_images/5/web/461000-461999/461913_17_full.jpg



http://images.cardomain.com/member_images/5/web/461000-461999/461913_18_full.jpg

[42F67N]

yamalube 2s if its oil injected 2r if your premixing it into the tank.

[John mendolera]

Your ytm 125 look's like a 1980-83 can't be exact unless you give serial # off steering neck.I say 80-83 because later 84-86 have a vented gastank cover.

[hondatrikesrule22]

Good find!If its been sitting that long,you will want to clean the carb,drain the gas tank,and new fuel lines and an air filter never hurt nobody.

[jeffwilson0]

Thanks for the quick reply's, I'll check the serial number next time I'm out there and post it.

This yamalube 2s that 42F67N mentioned, is it only available at Yami dealerships or normal parts stores? I'm pretty sure it's oil injected, it has an external tank under the seat, and the throttle cable splits into 2 separate ones just after the gas tank, 1 goes to the carb, and I'm not sure where the other one goes.

I tihnk it's a 428 x 60 chain but i'm not sure.

[Dan Tenn]

Yes, it is oil injected. Yamalube is sold only at Yamaha dealers. Any high quality 2-stroke oil should be fine to use. The other half of the throttle cable goes to the oil injection pump.

[TimSr]

Yes, it is oil injected. Yamalube is sold only at Yamaha dealers. Any high quality 2-stroke oil should be fine to use. The other half of the throttle cable goes to the oil injection pump.

Make sure the oil you select is suitable for injectors. Many of the high quality synthetcs are for premix only. Blue Marble is suitable for injectors. (my cheap comercial plug)

The chain is #520 like somewhere around 50 links, and its in your favor to get one about 102 or 104 and make two out of it. Otherwise youll have to cut down a 90, and throw half of it away.

[YamaChuck]

48 links for the chain.

[slippy4]

my 1980 had a #428 chain on it.....

[tririder]

The tank under the seat is the oil injection tank. It adds the oil to the gas for you so you don't have to. If you need help replacing the lines and you don't know where they go your local yamaha shop will show you a diagram. The year of your machine should be behind the headlight on the gooseneck. It should say..." This 198_ Yamaha..." The throttle cable splits in two because one goes to the carb to pull the slide and the other cable goes to the oil injection pump right behind the right footpeg.

[atckowalski]

I think that you may be trying to start it without oil in the oil tank.Try filling it and than make sure that you bleed the air from the oil pump line before you try to start it.Does the engine turn over?

1st trike, yt125

[jeffwilson0]

The tank has plenty of oil in it, I checked that. If I let it sit for a couple of hours it fires right up again first pull. I didn't want to force it to start by pulling it, or run it any longer as I know that oil is at least 10 years old. I figured I'd change the fluids and give it a tune up before I tried again.

How do you bleed the air from the oil pump? Is there a bleeder screw? This would be handy info to have when I do change it.

[42F67N]

Ive allways used yamalube in all the bikes ,my blaster and now my atc 70

[350XXX]

here is a link with the specs for the YT125 yamaha:http://www.accwhse.com/XYT125.HTM

[350XXX]

be careful trying to pull start a bike that has been sitting that long, you can bend the rod, just ask the guy i bought mine from!lol. here is a link for a service manual for the trike. this is all i have. http://store.yahoo.com/motobooks/yamat34wheel.html

[350XXX]

one more tip, the bolts in the motor are VERY soft. i had to use a 3/8 drive pnuematic impact with a 1/4" socket and a 1/4" phillips hex bit to break most of them free.

[nuttybazerko]

i'd say that is an 81 or newer unless someone changed the headlight. mine was a 1980 and the headlight had less plastic around it and it was more rectangular so to speak. those machines do awesome wheelies! mine never had any problems with the oil injection and it seems i hear of a lot of oil pumps going bads on blasters. what did yamaha start doing wrong?

[wheelercrazy]

hello can you please send me picture of the carb hook up to the motor.
i have yt125 with alot holes hanging from the motor thank you my email lemitchell@cableone.net

[rustbucket]

your rings are whooped it gets hot then loses compression and dies. looks like a 81-83 since it has a shroud around the headlight as the 80 model did not. looks like its in good shape. these trikes were pretty tuff although mine didn't last long I lost the air filter while mudd bugging the rings and gaskets and reeds are available,however the reeds are a diffrent design they are now two petals. They cost about 75 american

[Dan Tenn]

You can order replacement boyeson power reeds for this model at Dennis kirk for $28.

http://www.denniskirk.com/jsp/product_catalog/MMYSkuDisplay.jsp;jsessionid=25ZRHK0ZULGV5LA0WTISM 4VMDK0NCIV0?leafCatId=11104&catId=111&store=Main&mmyId=6226

[rustbucket]

now that i read my previous post i see my mistake the whole top end job set me back 75 bucks

[edog]

Nice Tri Moto,looks to be in good shape.