Just Got a 1977 400

[tjcin]

Tonight I bought a 1977 400 from a friend of mine.  Bike is going to be a nice rider with a little work.  One thing I noticed is a decompression device but it seems to be missing a lever assy and a cable.  I kicked the bike over and I am pretty sure I will need the decompression system to work, WOW!  Anyone have a resource for these items?  Thanks Tim C

Tim C
1984 Yamaha RZ 350
1973 Honda CR 250M
1970 Honda CT 70H
1970 Yamaha RT1
1972 JackPiner X 3

[brian kirby]

Lots of them on eBay.

Brian

[Kip Kern]

Or check Al.  I have a 76 400 and can start it sitting on the bike with no decompressor installed.  Just get the timing spot on and deck height correct and she will start OK.  Bing 38mm.  Have fun!

[tjcin]

Thanks for the info guys.  I did check Ebay and there were lots of items for late model KTMs but nothing for this bike.  I will keep looking and also call Al.  If you know anyone who might have the lever assy and cable they might like to sell, keep me in mind please.  Tim C

Tim C
1984 Yamaha RZ 350
1973 Honda CR 250M
1970 Honda CT 70H
1970 Yamaha RT1
1972 JackPiner X 3

[chicagojerry]

tim. there is a head mod that carl cranke used to do "back in the day" it takes some material out of the dome of the head lowering the compression a little.. it makes them MUCH easier to start and a much more controlled power band. i do it to virtually every 400 motor that i rebuild. jerry birky can still do it and he usually monitors this site. its usually less than 50$
chicago jerry

[tjcin]

Thank you Jerry.  Sent you an email regarding another topic.  Thanks Tim.

Tim C
1984 Yamaha RZ 350
1973 Honda CR 250M
1970 Honda CT 70H
1970 Yamaha RT1
1972 JackPiner X 3

[chicagojerry]

tim. i didn't get the email.    send it to me direct.
[email protected]
chi jer

[tjcin]

On its way.

Tim C
1984 Yamaha RZ 350
1973 Honda CR 250M
1970 Honda CT 70H
1970 Yamaha RT1
1972 JackPiner X 3
1977 MC 5 400

[tjcin]

Anyone have a picture of the correct tank for this bike?  It has a Hi-Point tank on it and it is modified so the forks won't damage it.  I would like to save the tank that is on it and replace it with the right one.  Please be easy on me, I am new to Pentons.  Thanks

Tim C
1984 Yamaha RZ 350
1973 Honda CR 250M
1970 Honda CT 70H
1970 Yamaha RT1
1972 JackPiner X 3
1977 MC 5 400

[brian kirby]

GS or MC5?

This is my MC5 with the stock 2.2 gallon tank.



This is the same bike with the 3 gallon GS tank.



Brian

[Andreas Piepke]

Hi Tim,

I have a decompression valve with cable and lever. Send me an email if you still need one.

Andreas

[tjcin]

Thanks Andreas, I sent you an email through the forum.   And my bike is an MC 5.   I will post a picture tonight.

Tim C
1984 Yamaha RZ 350
1973 Honda CR 250M
1970 Honda CT 70H
1970 Yamaha RT1
1972 JackPiner X 3
1977 MC 5 400

[Steve Minor]

If it's a true 77, it should have orange plastics with white fenders. And the GS and MC tanks have different shapes. Post the number stamped on the steering head and it can be dated.

[brian kirby]

I think it is the '76s that were orange and the '77s MC5s followed the size coloring of prior years, but the GS6s were all orange in '77.

I dont think I have ever seen an MC5 with a Hi-Point tank on it before.

Brian

[454MRW]

77 MC5's were orange with the "C" shaped tank decals, except for red West coast bikes. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1978 KTM 250'S
1975 Can Am 175 TNT 250 conversion
1976-78 125-400 RM's & 79 PE250 Suzuki & 2012 DR650
2007 CR125R Honda
1977 MC250 Maico