70 engine swap help

[Yamahajake]

Hello there i have a 1982 honda 70 that i am putting a lifan 125 into i found a lifan kit my question is how much modification can i expect? and what do you use for a head pipe? thanks jake and ill have more questions later

[oscarmayer]

well, once you have the correct kti to bolt it in, worst is wiring harness midification. then battery mounting position. after that rest is much easier. you should be able to use your stock hed pipe, but it will be a bit small being for a 70, so you may look at trying to get a performance ATV 125cc muffler form a china shop to use for it. it will be a larger pipe and will provide better performance.

good luck and most of all, have fun!!!!

[murfman]

here is a rundown of things you need to consider:
Intake manifold, the one that comes with the motor is too tall and will hit the tank. The 70 manifold ports are tiny and will choke the motor. I used this manifold I found on Ebay it fits great:http://www.ebay.com/itm/BRAND-NEW-25MM-INTAKE-MANIFOLD-INTAKE-GASKET-HONDA-XR50-CRF50-NEW-/261040636867?_trksid=p4340.m185&_trkparms=algo%3DSIC.NPJS%26its%3DI%26itu%3DUA%26o tn%3D5%26pmod%3D400298398378%26ps%3D63%26clkid%3D9 112004319608624259
***NOTE: I am running fiberglass tanks from sterdy products, so I am not 100% sure the above manifold will clear the stock tank***
Kickstart: Will hit the fender and / or the rear tire. I opted for a 110 CC Electric start motor from Hooper imports. The 110 has plenty of power to haul my 300 Lbs around and is still a wheelie machine. The reason I chose the 110 is the starter is on the bottom to leave more room for the carb and air cleaner without having to miount the carb forward on the motor. You can also swap the original pull start on using the original 70 stator cover and a spacer from DrAtv or E-bay

Thumb throttle: THe original thumb throttle will not have enough stroke for the new carb. I bought one of these:
http://www.ebay.com/itm/Throttle-Lever-Thumb-Controller-Assembly-ATV-Quad-Pit-bike-110cc-150cc-TaoTao-/120902089083?pt=Motors_ATV_Parts_Accessories&hash=item1c2653797b&vxp=mtr

Carb: The ones that came with my motors had the fuel inlet and choke on the wrong side, I am running this carb:
http://www.ebay.com/itm/261015450706?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649
I still had to cut off the lever on the choke and glue the round cap on the the clutch arm so I just twist the knob to apply the choke.

For the exhaust I bought one of thses and added one bend to make it fit the 70 frame:
http://www.ebay.com/itm/160731570945?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

I went a different route and I am running ballistic 4 celi batteries, they are spendy, but they are sealed and less than one pound. They also hold there charge very well while stored. I will get a pic of my battery mount, I mounted them to the side of the frame over the chain behind (under) the fender.

Hooper Imports has nice wiring diagrams on their website to help make the wiring easier.

[Blown 331]

murfman, can you post pics of your bike? Especially the exhaust.

[murfman]

http://i184.photobucket.com/albums/x205/murfman_photo/ATCs/D4E3A9F7.jpg
http://i184.photobucket.com/albums/x205/murfman_photo/ATCs/FC418BD7.jpg
http://i184.photobucket.com/albums/x205/murfman_photo/ATCs/5DD9C4E9.jpg
http://i184.photobucket.com/albums/x205/murfman_photo/ATCs/7C2E5564.jpg
http://i184.photobucket.com/albums/x205/murfman_photo/ATCs/30E93BFB.jpg

[Knobby Addict]

Yea that $50 Chinese exhaust is great for custom fitting to your machine (PCC motors source). I have used it succesfully in two z50/lifan 125cc projects so far, bent cut and otherwise modified to fit. I plan to put it in my atc70/lifan 125 too... my only complaint was the excessive noise from the Straight through design. It is ridiculous and unecessary = no HP gain and obnoxious....like a Harley! I did come up with a sweet cheap mod to drop the Db in half...I'll verify that if I ever remember to get the Db meter from my buddy. 1/2 hour in the local plumbing store and I had a tight fitting copper end reducer to a 3/4" copper pipe. I soldered a 6" capped (at the forward end) "spark arrestor" with several different size holes along the 6" copper pipe to change the frequency through the pipe. It all exits through a 3/4" copper fitting at my angle of choice. About $28 to tune the exhaust. Zero loss of power without pissing off the tree huggers and not sounding like a Harley....148380148381

So for less than $80 all the local kids are impressed with the $200+++ "big gun" pipe sound.

[Tri-ZNate]

And if money is no object hondaatc70.com has everything you'll need including an exhaust that will bolt right up and can be made for Honda or klx port angles. They have up to a 150cc electric start motor. Just enough to have a blast

also depending on the motor you have, you may have to trim the frame a tiny bit by the lower mount so the engine can rotate up during installation

[oscarmayer]

hey murf, that's the same exhaust we ru on my son's older 1st gen prototype racing ATV. lol, it works good except the dam muffler keeps popping off during races!! :< i am about to woller it out so it will fit the exhaust a little looser and slide on deeper then use alloy tape to seal it.

[Yamahajake]

thanks guys got my new tires in can got the 70 tore down (in my living room) and buying engine and other parts this weekend