1972 Honda CL70 problem

montanaman · Post by **montanaman** » Fri Sep 23, 2011 5:15 am

Well I strated with the head and valves, I took it apart and started cleaning it up. I have a couple pics so you can take a look and let me know what you think. I am ordering the other things you mentioned. I was just going to re-use the valves, but may just order a couple. I measured the cylinder and it was 46.75mm so i guess I can either do as you said and have it honed maybe to fit a larger piston? or pull it out clean it up and put new rings on it. I am going to do the other things like the oil seals on the gear shift and kick start as well.
I really appreciate the input and help, This is my first time doing this and you have been a great help,

montanaman · Post by **montanaman** » Fri Sep 23, 2011 6:20 am

Some more pictures of the cylinder.

will1972rupp1 · Post by **will1972rupp1** » Fri Sep 23, 2011 8:55 am

blue flame in the carb sounds like you need a valve job,

i would try a hone first, but if there is any pits from rust left, i would go 1st over with the jug, you will need to buy the 1st over piston & take it & the jug to have bored & honed at you local shop.. also i make sure I bought a dome piston, or you can buy this kit on ebay. good luck.

http://cgi.ebay.com/ebaymotors/_W0QQcmd ... Q5ffviQ3d1

montanaman · Post by **montanaman** » Fri Sep 23, 2011 9:56 am

Thanks for the info. Why a dome piston? is it possible to hone the old one out and put in a new piston? I was trying to keep it as original as i can, but if its better to use a dome, i certainly will.

montanaman · Post by **montanaman** » Fri Sep 23, 2011 12:23 pm

Well I measured everything and suprisingly everything was with limits. The cylinder is not that bad at all either. So i guess I could go the cheap route and just get some new rings, or get a ,25 mm over piston and have it honed. I want to go the easy route, but I'm sure I will regret it. Here is a couple pictures of the cylinder.

will1972rupp1 · Post by **will1972rupp1** » Fri Sep 23, 2011 3:33 pm

it looks like you have the dome piston, not all they sell are dome, just make sure of what you are buying, good luck.. make sure you put all of the o rings back in the right place if you haven't done this before..

montanaman · Post by **montanaman** » Fri Sep 23, 2011 4:31 pm

Ya, when I pulled it of a couple fell off so I will have to get in the book and make sure I put the new one correct. Also, the top 2 rings on the piston are immobile], seized up, so re-using the piston was out of the question. I now understand why you reccomended the kit you did, would be a heck of allot easier to go that route. I just bought a standart piston, rings, clips and think I will try to get by without honing it. These things can get expensive, but I will have an almost new 72 cl70. I'm looking forward to getting it all done. I have all the OEM parts including wire harness. After I get it running nice, I plan on a paint job and new spokes as well.

will1972rupp1 · Post by **will1972rupp1** » Sat Sep 24, 2011 1:47 am

i would do a quick hone job so the new ring seat, i would also get the valves & seats cut, or at least new valves & the seats cut.. this will help it a lot, the valves will have a good seal, i would take it too your local shop & see if they have the pilot tool & the seat cutter, & if they do get the head apart all the way & ask them to clean & glass bead it, it will be like new,

montanaman · Post by **montanaman** » Sat Sep 24, 2011 6:13 pm

Are CT70 and CL70 valves the same?

Smithers · Post by **Smithers** » Tue Sep 27, 2011 5:55 am

Not sure on that one. Don't want to guess.

BUY NEW PISTON AND RING KIT AND VALVES!! That cylinder is thrashed. No way I would put it back together with just new rings.

If I lived in a third world country I would do some old school tricks to make things work but here in the modern world there is no reason you can't make it like brand new.. actually better than new for very little money. I know you are thinking about saving the money but a new piston and ring kit and valves won't break the bank and then take those to a machinist and it shouldn't cost you much at all to have him surface the cylinder. The valves you can lap into the valve seats in about 5 minutes and not break a sweat.

The bike will run so nice! Makes me want to go rebuild mine now just for drill!!

montanaman · Post by **montanaman** » Tue Sep 27, 2011 5:27 pm

Smithers, you make me laugh : ) Got new piston and valves today, heading to machine shop tomorrow. Found someone to do the job.

montanaman · Post by **montanaman** » Wed Sep 28, 2011 5:25 pm

So I figured I would get some painting done while i'm waiting on parts. I am following Smithers' advice to the tee. I found a great dremmel atachment that takes the old paint and primer right off! PWill post pictures after primer and paint.

Smithers · Post by **Smithers** » Fri Sep 30, 2011 3:24 pm

Ah nice that bike is going to run great after your all done. Nothing better than having a 50 year old bike start right up in a parking lot while 10 people are watching you leave. They will be expecting to see you do the kick start slam dance but instead you will just hit the little button and glide away.

montanaman · Post by **montanaman** » Fri Sep 30, 2011 7:19 pm

Kick stand huh! i will keep and eye out. Well here is the first coat of clear coat, and got my head and cylinder back today.. looking pretty nice. Just got to finish painting and then I will be bothering you guys trying to put it all back together.. : )

will1972rupp1 · Post by **will1972rupp1** » Fri Sep 30, 2011 7:28 pm

looks good they cleaned up well..