A few questions about my little 71 Honda SL 125

[shspvr]

So I finally have enough of the parts so that I can begin putting the engine back together and most importantly I have a Clymer manual. The gasket set I have says there is no need to use any gasket sealer. The manual says some gaskets sealer and some do not. I have yet to find in the manual which ones do and which ones don't. I did not crack open the gear box, so I am strictly talking about the top end. Which if any gaskets need sealer?

and

Will motor oil work as an assembly lube? If not, any recommendations?

Thanks in advance for any help

H aka RRR

Do not use any Gasket sealer on you head gasket as for the base gasket just use Gasgacinch Gasket sealer and only need it in one area on both side of the gasket that if you pull the Jug and if you did then Pre-Oil the Piston and Cylinder, On Base Gasket you see U slot cut where stud bolt gose thur that is oil passassage for the cam it on back side on clutch side only do round that area, Now the Cylinder Head gasket make sure that install Oil Passage Seal (Look like a thick Oil Ring) it gose on a back side to there a dowl on the clutch side, then just use some assembly lube on cam lode and cam journals.

For mate cases this the best to use ThreeBond 1211 Gasket Sealer or No Gasket Valve cover.

[Red River Rider]

Got it SHSPVR and assembly is underway. Thanks!!! Hope fully I will have some pics posted this weekend. This is a badly abused little bike that I am going to get trail ready. I think the little scoot will be happy with that. I have toned her back down to a 125 cc for the fiance's 1st bike and the 150cc jug is usable for a future rebuild. For now she's gonna be a restomod little trail bike. stay tuned for more including pics. I'm gonna do her up right and keep her in the family. Looking forward to mANY UPDATES.

[ernest t]

The cam journals should be smooth. I've had to replace the head where they were worn real bad.

This one along with the cam wwere bad.

[Red River Rider]

Yep Ernest T my journals and cam are in a bad way as well. I just don't have the funds to re[lace them at this time. Motosprtman had said earlier that manyan old SL died from low oil level and/or dirty oil. Mine suffered from both. I opened the centrifical oil filter and it was gummed badly, then I took out the oil strainer and it was at least 90% blocked. I am hoping that since it WAS running in this shape before, she'll run again. I am watching for parts that I need but I just can't afford 500 or so for new head, cam, rockers etc right now. I am about 75% done and we will see how she runs. As soon as I am able I will replace the whole valve train. Thanks for the advice.

[shspvr]

SL died from low oil level and/or dirty oil

Not just that but also CB, CL, TL and XL

Most common problem is people not changing there oil and clean out the centrifical oil slinger ever few years on a non oil filter.

As for Head you can get a wide ranges of years and model starting with CB, CL, SL 1971 to 1974 and TL, XL 1974, 1975 in 100cc and the 125cc Haed can also be use 98% parts form each motor can be swap over

What not a direct swap are

Crankshaft there is a diff in rod for piston pin size 100cc (14mm) and 125cc (15mm).

Cylinder it the Bore Size but with the rigth piston you can use a 125cc Cylinder on 100cc motor.

Piston there is a diff in piston pin size 100cc (14mm) and 125cc (15mm).

The Carburetor are same the only diff is in Main Jet and belive if recall rigth also the Needel.

You can find every thing you need on ebay just ask the seller to sent you good picture of cam journals

If see a heavy dark black burn in oil on alum like in that picture above on around journals then more then like that head trash, you want see little ligth to midd in a Caramel or Tan color inside then it ok or none at.

Edited October 3, 2011 by shspvr

[Kev_XR]

I ordered the 150cc kit and the 125cc kit listed on eBay.

I have not had the time to rebuild my TL125 motor.

Warning: The older TL125 motor cases are too small to allow the 150cc cylinder sleeve into the cases. I am not sure if your SL125 has the smaller opening cases or the larger ones. No problem with XL125 cases. I'll see if I can find the dimensions.

[Kev_XR]

The cam journals should be smooth. I've had to replace the head where they were worn real bad.

This one along with the cam wwere bad.

Thanks for the update on how to tell if the cam bearing is OK.

I've been trying to figure out how many parts on my TL125 motor need replacing. Piston and cylinder for sure. Cam guides, head, valves, etc. I need to make sure they are good or replace them. Some of those parts are getting harder to find.

I have two motors for parts. XL125 and TL125. If I ended up with two running motors, I would be more than happy. ?

[shspvr]

I ordered the 150cc kit and the 125cc kit listed on eBay.

I have not had the time to rebuild my TL125 motor.

Warning: The older TL125 motor cases are too small to allow the 150cc cylinder sleeve into the cases. I am not sure if your SL125 has the smaller opening cases or the larger ones. No problem with XL125 cases. I'll see if I can find the dimensions.

Dose the case half have the gasket there?.

That or some body at Honda forgot add gasket on first machining.

Yes I for got if the is 100cc cases then case machining was is needed

[Red River Rider]

I ordered the 150cc kit and the 125cc kit listed on eBay.

I have not had the time to rebuild my TL125 motor.

Warning: The older TL125 motor cases are too small to allow the 150cc cylinder sleeve into the cases. I am not sure if your SL125 has the smaller opening cases or the larger ones. No problem with XL125 cases. I'll see if I can find the dimensions.

The little SL I bought a few months back came with a 150cc kit installed. I have since purchased a 125cc kit and installed it. So, the SL's will accept the 150 kit. I may use the 150cc cyl. I have when I do a complete rebuild in a few months.

[Kev_XR]

I think the big difference is if your motor was a 122cc or 124cc cylinder.

My 1973 TL125 has the 122cc cylinder.

The 150cc cylinder kit will not fit into the cases, the liner is too wide.

Also, I have an XL125 engine, which has 124cc on the cylinder.

The 150cc cylinder kit will fit into the cases.

I bought a 125cc kit for the TL125 (122cc) motor and a 150cc kit for the XL125 motor. I am hoping I can get at least one, if not both motors rebuilt. Both kits cost about $60 each. Cheap.

Adding to the confusion, the later TL125 motors have 124cc cylinders and two piece heads.

All of the dimensions of the kits on eBay are here.

https://www.thumpertalk.com/forum/showthread.php?t=988521&highlight=gongyu

[Red River Rider]

Just looked at the original cylinder (bored to a 150cc) and it says 122cc on the casting. Looked at the new 125cc cylinder I have installed and it says 124cc. So I guess my little SL is immune to the problems you're having. I am thinking you could have your 122cc jug bored for a 150cc piston and ring kit if you really want the TL beefed up a little.

I just measured the O.D of the 122cc sleeve where it slides into the crank case and it measures 67.52mm. To late to measure the same on the 124cc, it's already installed. I did notice that the new 124cc sleeve was considerably longer and fits deeper in the crank case. I turned the engine several times at the flywheel and nothing is hitting so I guess it will be OK. I just thought it was a little odd.

Had to set the rockers by feel. The cam journals and lobes are worn badly and I could not get it right with feeler gages. I just set them so they had a little slack.

[shspvr]

Adding to the confusion, the later TL125 motors have 124cc cylinders and two piece heads.

Keep in mind that 125cc where base on 1970 Motosport SL100, SuperSport CB100 and Scrambler CL100 motor

Check the Frame VIN number to the Motor VIN they should match

From what I recall Honda had all one piece heads from 1970 to 1975 in 1976 model was the frist of two piece heads

You find every model honda ever did here even some odd ends stuff

http://www.motorera.com/honda/index.htm

Edited October 4, 2011 by shspvr

[Red River Rider]

That's a great link SHSPVR. Good info. What part of Oklahoma do you call home?

[shspvr]

That's a great link SHSPVR. Good info. What part of Oklahoma do you call home?

Coleman, Oklahoma about 20 miles north of Durant, Oklahoma

[Red River Rider]

Coleman, Oklahoma about 20 miles north of Durant, Oklahoma

yep I know right where that is. I am from the Gainesville Texas area. Spending a year or so in Arkansas while my fiance gets her 2nd degree. I am supposed to be back in North Texas in a few months. Maybe we can do some riding when I get back. Way back in the day I rode Bulcher (near Muenster) and Dripping Springs (near Walnut Bend) and Blues Bluffs (near Thackerville OK) With any luck I will be back in Tx by Sept 2012.

Edited October 5, 2011 by Red River Rider
drunk

[shspvr]

yep I know right where that is. I am from the Gainesville Texas area. Spending a year or so in Arkansas while my fiance gets her 2nd degree. I am supposed to be back in North Texas in a few months. Maybe we can do some riding when I get back. Way back in the day I rode Bulcher (near Muenster) and Dripping Springs (near Walnut Bend) and Blues Bluffs (near Thackerville OK) With any luck I will be back in Tx by Sept 2012.

I take that ref to Red River Motorcycle Trails to near Bulcher? I have not been there.

This frist year in Oklahoma for me so far I only got to ride at Murry Lake ATV Park next year I hope to try Crossbar Ranch and Red River ATV Park next year.

I come from Ravenna, Ohio where we want to a place called wellsville trail and it was one of must kicka$$ place to ride some smooth hills, lot rough rocky hills:banana:, some very kicka$$ hairy hills:jawdrop:, and some flat run of mill trails:ride:.

[Red River Rider]

I take that ref to Red River Motorcycle Trails to near Bulcher? I have not been there.

This frist year in Oklahoma for me so far I only got to ride at Murry Lake ATV Park next year I hope to try Crossbar Ranch and Red River ATV Park next year.

I come from Ravenna, Ohio where we want to a place called wellsville trail and it was one of must kicka$$ place to ride some smooth hills, lot rough rocky hills:banana:, some very kicka$$ hairy hills:jawdrop:?, and some flat run of mill trails:ride:.

Shsrvp- I rode Bulcher way back in the 70's before it became an official trail park. Used to be good riding there. Ballsy hills and tight trails and you could get on the sand bars down by the river and do 70+ mph for a mile or more when the water was down. I will be back in Texas late next summer for a year or so, maybe we can get together and ride. I know where there is some state land where folks still ride for free. Used to love riding in the cold rainy falls there.

And by the way.... I'm wondering if a TL 125 header will work on my little SL. The SL I had years ago had an exhaust that ran above the crank case. Thought I might try and do the same with the one I have now.

H

[shspvr]

Shsrvp- I rode Bulcher way back in the 70's before it became an official trail park. Used to be good riding there. Ballsy hills and tight trails and you could get on the sand bars down by the river and do 70+ mph for a mile or more when the water was down. I will be back in Texas late next summer for a year or so, maybe we can get together and ride. I know where there is some state land where folks still ride for free. Used to love riding in the cold rainy falls there.

And by the way.... I'm wondering if a TL 125 header will work on my little SL. The SL I had years ago had an exhaust that ran above the crank case. Thought I might try and do the same with the one I have now.

H

Ok sound good

If the TL 125 is a One-Piece Head that look just like SL Head then it will work with SL motor and other model to it the Two-Piece Head that can not used.

The exhaust that ran above the crank case or below crank case there should be the some size pipe the main diff had do with rigth hand side cover which only TL and CL had there exhaust that ran above the crank case or if was aftermarket pipe where you get both way just depend on who made them.

[Kev_XR]

TL125 parts are becoming rare and more expensive.

The good news is Honda like to reuse parts on many bikes.

Here is how check to see if the part on my TL125 is a common part from a CB, CL, SL, etc.

Look up the part, such as the header.

I often use the ServiceHonda.com website.

Look up the part number here:

You are looking for the middle 3 digits.

http://www.kaila.net/tl125/tl125partcode.html

See if that part was TL specific or from a CB (millions of those parts around.)

[Red River Rider]

Well, everything is back together and after letting the little SL sit over night so I could check for any oil leaks..... no spark:banghead:. So tomorrow it's off to buy a multimeter so I can start the search. I guess it's for the best since electrical stuff is where I need the most education. At any rate, anyone got any short cuts to narrowing the search? Any help as always is greatly appreciated. By the way I installed new coil, plug, condensor and the points look good to me. I did install a used but good looking wiring harness and rectifier. I checked the fuse and will by pass the ignition switch tonight. So where would you begin?