my journey begins and never ends

I'm little confused about my intake size, I received my complete gasket set yesterday. there were two intake gaskets.

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looks like one is 30mm and the other one is 40mm, so which one do I need.

the 30mm
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too small.the other one was a bit too big, so I customized it a bit.

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so it seems to fit well now, plenty of gasket coverage.

is this normal for a china doll? I still don't know what size my intake is.
 
The most common intake spacings are 32 and 40 but there are some out there that are 35mm and I got a few with the 35mm bolt spacing over here, basically it just means make my own gaskets or do a little trimming if I use an "off the shelf" gasket. I've had to trim some intakes to work with these 35mm cylinders as well... They usually come with an intake, no problem there, but when upgrading it means a little extra dremel work. I got a 35mm intake bolt spacing on my latest project and had to do this to make a 32mm aftermarket intake fit it... Basically took a cutting wheel and cut the ends in toward the holes so they are open but slotted now, the aluminum on this intake is 5/16" thick so it don't effect the sealing at all... I wouldn't use this method on a thin flanged intake...
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Thanks Davezilla, that clears it up a bit. well, I have a 40mm boost bottle...

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I will probably find a washer and longer screw for this, it snugs up well right now though.

the throat of the boost intake is smaller than the intake that came with the engine, kit intake on left

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the gasket is fitted to the port ok, a lot better than this

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so is this ok? if I use it, should I bore out the intake to match the gasket?


on another note, I tried ramping the piston to the tranfers, and I wanted ramps to be angled to the intake

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so it's not very asymmetrical. can I even run it like this? or too off balance?

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I also managed to get the screw out with a friends impact driver, although is still took quite a few good taps to break loose. so now I can split the crankcase. then...what's a flywheel puller? Doh! well it's necessary to crack the case that's for sure. and it's not carried by most of the normal stores. found one on amazon, 19mm x 1 but I'm not sure if it's that or 19mm x 1.5 that i see out there as well.

I might be able to get one macgyvered if I know the inner number.
 
That'll work just fine, it's best if the ramps are as equal as possible to each other on each side but I've seen a lot worse looking ramps and they worked just fine...
 
thats good to know, I thought it was a wasted piston. Now I've got to get this thing matched, built and mounted. and the sooner the better.
 
Yup... just pre lube the bearings and the rings as you put everything together, motor oil works just fine if you plan on starting it up soon. You can pre lube with stp if the engine is going to sit for a few more days before starting as the stp will stay put much better with it's honey like consistantly and it'll wash out easily soon after the engine is started. I use stp to pre lube all 4 stroke engine bearings during assembly as well as filling the oil pump with it so it can get a good prime before the first startup. For 2 smokers it works great to keep the rod bearings lubed until the engine starts and then the gas/oil mix will wash it out of the way quickly.
 
thanks Davezilla, I have the high performance semi synth lucas oil, but I will be trying to mount and start with in a resonable time. I started work again, so the project will slow down a bit. but I'm gonna get er done.

I was asking around about balancing my crank, but I don't think I'll bother. I really want to wrap this up and get her rolling, and I'm impatient to find and wait for someone to do it.

I have started matching my ports, and ya there is alot of extra material compared to the jug. I still have a little more to go and it's hard to see the excess material in a photo, it's hard to see with the eye. but gentle braille you can feel the difference.

now I know alot of people have looked at this thread, and thought that I must be stunned for never even having ridden a motorized bike and tearing a new engine right to pieces and practicing my shaping skills. I had my reasons, as stated early in this thread. but it's been alot of fun, and gratifying. until I went to split the crank case. no matter how well I match the ports, I wouldn't do it again. but of course having had that memorable experience, I will do it again.

all that said I have to thank Legwon for his help and encouragement and Davezilla of course as well as Fred for his video and gasbike for their cgi vid. and I'm only at a pile of pieces at this point. yeehaw
 
You're welcome and your work on the porting and matching will make the bike all the more enjoyable since everytime you crack the throttle you can tell yourself "I'm the one who made it do that" or when you can keep up with traffic and the cars when taking off from a green light... and especially when you see other motorized bikes not quite able to take off as good or pass one up just cruising when they're already maxed out...
I don't compete with my bikes but I do like being 10 mph or quicker than most others if I see them on the road. I have seen one guy riding one close to my shop but I hadn't seen him on the road the same time I'm riding, but I saw him at a stop light and noticed he had a fred head and some other goodies installed.
 
well I'm pushing through I'll get there, and I have started to get an idea for mounting. a co worker is a machinist who seams interested in the project, I just need to nail down the measurements. once I mock it up with my magyver rear mount I will get a pic ask if the placement looks good.

forgotten about balancing, from what I can find out you can only balance for specific rpm range anyways. so whatever, onward and upward
 
For the rear mounts I've just used 2 of the aluminum rear mount blocks with longer studs to make a much more solid rear mount, it worked and was a lot more rigid than the factory steel strap type. I did find something really interesting this morning, this guy on facebook sells some really nice mounts but I need to find out if they're made for different sized frame tubes etc... https://m.facebook.com/profile.php?id=733210093450674 He does have some really nice goodies on his facebook page
 
ya, he has some shiny stuff there. I imagine the two park plug set up is one of debate, whether it helps or not. I would have thought as long as you have a strong spark you'll get good ignition, and boom is boom no?

about mounting, I think my machinist friend should be able to come up with something decent. so I'll go that way for now
 
Yeah, the twin plug thing has already been proven not to make any extra power but it looks cool and it sells... and if someone is going from a stock head to this or any high compression head they will feel a difference.
It does have some advantages tho in the sense that you can run a lot less timing advance since it burns the fuel twice as quickly if the plugs are placed far enough apart so the peak cumbustion pressure happens sooner. If you remember those 80's Nissan 4 bangers that had the dual plug heads, the timing was set to only 3 degrees instead of single plug engines where the timing was set somewhere around 12 to 15 degrees initial advance. So it pretty much makes the engine detonation proof, supposedly does a more complete burn of the fuel since the timing is retarded back by around 10 degrees as well as there being 2 points of combustion, so it could work more effectively if the timing could be adjusted to compensate for this.

As far as power goes, any good high compression head will make a noticeable difference from just off idle all the way to redline. I still like the 6cc Fred heads best for my builds since they're pretty versatile, the extra power is definitely noticed, and fred sells them cheaper than the knock offs. I do like this guy's heads tho since they follow the lines of the engine really well and have nice combustion chambers, but the fred head will still keep things cooler due to it's huge mass compared to stock. I don't think one would run into overheating issues with this other head tho, unless they're breaking in a new engine in 100 degree heat, but it'll still do a lot better than a stock head.
 
I have been eyeing the Fred head for the future, I also like the head that Jakes does. Problem is I want to install a shift kit and I have read that a high compression head can make it almost impossible to start with the shift kit. Can I get a replacement head that doesn't increase compression but increases cooling?
 
You can get the Fred head anywhere from 5 to 8cc's, I prefer the 6cc as a good "all around" high compression head, it gives a good boost to the compression ratio, but not so much that it's hard to turn over or that one would need to run race fuel just to keep it from pinging.
I've been using a pull starter on mine and it pulls over fairly easily and usually starts on the first or second pull in the summertime or when the engine is warmed up, but in the winter when it's down in the 30's here it can take up to 4 pulls before it starts, but it's never took more than 4 pulls to start the engine even in the cold with a cold engine. I would recommend the pull starter to anyone who has a shift kit, centrifugal clutch, or just dont like bump starting the engine, they're cheap, they don't add a lot of rotating mass to the engine, and they're reliable for the most part.
 
well first things first, so I got to get her rolling. then I'll think about heads, shift kit, suspension forks, better exhaust etc...

my next days off I should have the engine reassembled and be working on fab'ing the mount.

I was reading a posted link from the thread about engine break in, and the author said the break in oil you use should be what you plan on using, even semi synthetic.
will that prolong the break in period because the synthetic is too good?

I have also seen adjusting the clutch arm, so that it is angled more into the engine to make it "smother and easier to operate", any thoughts about that?
 
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For the break in I prefer to use a good non synthetic oil like Castrol or shell Rotella for the first gallon of mix, then switch to your favorite synthetic 2 cycle oil. The echo weed whacker oil is good stuff or any other chainsaw or yard equipment 2 cycle oils will do just fine. I like opti2 a lot too and have run my engine on that at 100:1, the bike definitely liked it and started real easy on it but I won't recommend it for high rpm use where more oil should be used in the mix. Most the oils mentioned above for garden equipment will do great at 32 or 40:1 and amsoil dominator racing oil is also really good stuff at your favorite ratio as well.
These engines aren't too picky tho so just finding a decent synthetic after the first few tanks will do just fine... I think I broke my first one in with quaker state 10w40 mixed at 32:1 then switched to opti2 at 100:1 after the first tank and it did just fine.
There's still a lot of debate going on about oils and ratios but pretty much anything you run in these will work unless you just run straight gas which will ruin your engine on short order... one of my friends in here has been just using plain 30 weight cheap oil in one with a cheap ebay engine and so far it's been running just fine... I'm not sure if he's doing this to see if it will work long term or just proving a point, but so far that engine is still running great.

Now for the clutch arm, the best ones are the longer ones that have a slight bend in the arm but if you don't have that one, or even if you do have the longer bent arm, I made up a roller setup for mine and don't even use that cable mount on the engine. Others have made side mounted brackets that point the cable straight at the clutch arm and get the same result as the roller... a very smooth and easy clutch.
 
Here's a pic of the roller I made for my clutch cable, maybe some of the others who just made a better bracket that points the cable straight at the clutch arm can post their pics... both methods work very well.
mine was made out of a screen door roller I got from home Depot and a piece of angle iron I welded a nut on for the cable adjuster and drilled to mount onto the clutch cover. I'm going to use this same one on the new engine I'm putting in the mountain bike but going to make something a little better looking for the road bike and the stingray, I might just make the bracket without the roller for the other 2 bikes since appearance is more important on them, but the roller is easy and cheap to make and set up on the engine. It works great too...

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so I cut the stinger down, and drilled the four holes in the end cap. I tried separating the clutch arm pieces, it was taking too much force and I chickened out. I increased the angle of the bend of the arm to straighten the path a little, not too drastic as I didn't feel like snapping it. I will ask my friend who's going to make the mount about a little roller set up for the clutch.

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been busy, but trying to keep it going.
crankcase back together
gas tank studs sealed and reinforced
rear sprocket installed on wheel
throttle, clutch, kill button mounted. swapped 7 speed twist shifter to left side upside down. kept original grips, much nicer and sized for the shifter.

it's coming together
 
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