125 -> 150 is it a straight swap?

[Tomu80]

I plan to do a swap from 125 to 150. Does anyone of you guys know for sure is it only a case of swaping a cylinder & piston set (with rings, head gasket etc.) Will it work well without any ECU, head or throttle modification? I don't want any bigger cylinder like 163 ccm - just an ordinary 150 ccm.

[you you]

I plan to do a swap from 125 to 150. Does anyone of you guys know for sure is it only a case of swaping a cylinder & piston set (with rings, head gasket etc.) Will it work well without any ECU, head or throttle modification? I don't want any bigger cylinder like 163 ccm - just an ordinary 150 ccm.

Cue Gn2

[chucktuna]

watching this space....

Interested to know some of the answers to these questions also..

But the way you have phrased the question is a bit misleading.
When I think of a swap, I thing of a complete drivetrain changeover.
You're asking about parts interchangeability between engines...

In either case I think the ECU would need to match the major electronic components and sensors of the engine it was designed with.

[Mgalutia88]

It's not a straight swap. Takegawa and yuminashi sell seperate kits for 125 and 150 engines for a reason. Connecting rod differences I believe. What I mean is they sell two different versions o the same displacement kit.

[waspmike]

Tomu,

Mk1 version or newer Mk2 version?

[Tomu80]

MK II version. I'm wondering if when I'll buy mkII 150 cc set - do I need some other mods to get it done.

[waspmike]

It s of course up to you but I think I would improve the exhaust first and fit an aftermarket variator, then a cam shaft. Before venturing into the realms of barrel swapping..
Exhaust and a variator will make available about 13 hp (12.945) , then a little bit for the cam. Stock 150 is only about 13.5. This without a major engine dismantle.

[Tomu80]

Variotor won't give you any extra hore power... in fact it gives you nothing (imporves acceleration for the cost of Vmax or vice versa).

[dem0nk1d]

Variotor won't give you any extra hore power... in fact it gives you nothing (imporves acceleration for the cost of Vmax or vice versa).

Bull shhhh*t. Look at my max down hill speed on my 150. I'm NCY variator, pod air filter directly on throttlebody and bored out stock exhaust.

71MPG slight incline no tuck


77MPH down hill full tuck

[kramnala58]

What are those images from? Is it a smart phone app, a GPS unit, or a ....?

[dem0nk1d]

It's my phone GPS which is 100% as accurate as my car GPS. So there is no variance or discrepancy is the speed.

[mikelx5]

thats the ulysses right it is a really good one its the one i run

[dem0nk1d]

thats the ulysses right it is a really good one its the one i run

Mike, you are correct sir! Ulysses for Android! Also lets not talk about your top speed, even makes me depressed at hit 77mph. =)

[mikelx5]

haha mine is only about 75 flat tuck down a long hill i hit 80-85 lol

[BPT7594]

It would not work properly.. The 58mm piston from honda has a 14mm pin. Learned it the hard and painful way

[Oyabun]

Yeah. As BP said before me 125 conrod use 13mm piston pins while the 150 are 14mm.
If you wanna go bigger, do the right way. 164cc kits are not extreme at all and direct bolt on on 125 lower ends.

[BPT7594]

Or you can do a 150 if you're too concerned with safety. Just use a sonic piston. I ordered it from here. Hispeedpiston. Saved my ass.