If you are going to the trouble of a new ECM, then you should probably buy the race head that a few places are selling. Then you shouldn't need to do any porting. I'd also suggest going with a higher compression piston and cam, might as well get everything you can get out of the stock bore and stroke.
I'd like to keep the spare I bought, but if it really comes down to it, I could let it go for what it cost me. But consider the race head as something that might be a better choice.
I would check with Man in the Box and see if the head they sell will work with the stock bore, pretty sure it has bigger valves so they may not clear the cylinder walls. Someone else had a race head for the stock bore, but can't remember who had it.
Also can you post some pictures of what went wrong when you were porting? Like to see where mistakes are made so I can try to avoid them. Wondering if your head could be welded to fix the problem.
The only problem with drilling it and welding it agin is the other side is the spring seat and would be a headache to straighten out, I am going to ride it the next few days if the smoke comes back I am probably going to order a new guide, have the spot rewelded and install the guide, but i am still looking for another stock head for cheap lol
Greg_E touches on the subject in this thread & it is likely somewhere on the forum in bulk or fragments but I haven't seen it clearly stated; the dilemma for me right now is cost to benefit. What I am looking for is to gain what I will call "usable" power to:
1. Be able to cruse at 55-60 mph sitting upright with slightly lower rpm's ( through gearing change).
2. Overcome the occasional hill w/o getting run down by traffic.
3. Lift the front end easier.
Would I be able to get this with the base 143cc kit and TB head from Steady Garage w/o exhaust, fuel controller and other additional mods? We have all seen impressive dyno charts posted but they are usually box stock vs full out mod with big bore kit.
It looks like the 143cc kit will meet my immediate needs and can be something to expand on directly over time. Now to pull the trigger. Summer is going quickly and I need to strike a much better work/life balance and enjoy more of what we are all here for.
I purchased a 17 Z125 and it already had the flush mount signals, upgraded brake lights, etc. To have the bike safetied here in Ontario I need the original signals. I contacted the original owner and he had all items except the front signals, anybody have a pair of originals for sale? Thx for...
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