It was a NGK-BPR4HS spark plug. I am sure there are others but that is what was available locally. It has run quite well for me.Elmo,
I always enjoy reading your posts. They'd go like stink, eh? I never heard that one before. Ha! Thanks for your kind words and good advice. I'll disconnect the governor tomorrow and have a left over kit throttle I will change over to leather covered foam grips. I'm trying to read up and get up to speed on the HF motor. If I can't find anything on adjusting the valves perhaps you can point me and others in the right direction. What spark plug do you suggest? There is a beauty in what works well, is practical and straightforward, utilitarian... a machine that does what it is supposed to do. I like machines and I like your bike.
SB
Very neat build. I hope you'll break this loose and give it your own thread. It deserves it. I looked for your previous post & didn't see it... wanted to be clear on what engine that is. It looks like the 2.5 hsp. Is that possible you got that up to 8.5? I'd like very much to know more details of what you've done to that engine and I hope you have some photos of the changes you've made to it. This is what we need to know... how to get better performance and power out of what is already there.O.K., I know it's been a few months since I started The Low Rider project (motivated by following Elmo's Bike project...Thanks a bunch), but I've made some real progress. My goal was a Christmas test run but that looks like somewhat of a long shot. The rear suspension really slowed me up; hope 1-1/2" of travel is worth it. I went with a 10/24 - 10/44 jack shaft setup, that should push me 41.5 mph at 6000 rpm. Fast enough I think. (Elmo, what do you think of a 10.56:1 Ratio??) I made a copper exhaust with a baffle setup. Nearly no back pressure. It's not too loud but I may pack it with stainless scrubbers to quiet it down a bit more.
I have a friend and neighbor who races carts with these engines and he has been an invaluable resource; that's what its all about; bench racing and garage engineering. Motivated by my cart racing neighbor, I added a high flow air filter, changed the idle and main jets, ported the exhaust and of course removed all the internal governor parts from the engine. It should be around 8 1/2 HP. The bike i almost 9' long tire to tire... not very practical but maybe I'll do a commuter bike next since this one is not likely to be comfortable for more than a half hour at a time.
If anyone else is building a Harbor Freight / lifan project, and wants to do any engine upgrades or tuning I will be happy to relay any info I have found.
Just typing this post has fired me up!! It's Friday night but I'm putting down my beer and going back to the Garage!!
I also looked for prior posts; it looks like there were three posts total for this bike, all contained in this thread.Very neat build. I hope you'll break this loose and give it your own thread. It deserves it. I looked for your previous post & didn't see it...
SB