Motor build "Project: Type 86"

[wildbob]

The Type 86 is a Chinese hand grenade, and I couldn't think of a more fitting name for my motor build project. It's still in it's infancy, but the goal is to scratch build a motor for my buggy with 62mm jug, and 8mm of stroke, four valve Taida head with 23/22mm valves, forged 4V piston, forged Taida 8200 KDU crank, full Dr. Pulley kit for the CVT. My biggest worry is the gearbox. I have only the basic idea of where all the bits go, and I peeked in my whole motor which promptly puked it's tranny gears everywhere, so it's go big or go home at this point First off, yes, I know this motor is going to blow up.. This is why I'm not using my current (and now trannyless) trailmaster motor. Plus since it's new, shiny, and clean, I can build it inside where it's warm I may go with a 11 pole stator as well, as I'm thinking of going water cooled at some point and would need extra juice for pumps and fans. High power starter and accessories as well. I'll also be using the Taida case side with the oil cooler ports and their oil cooler with the Koso high volume oil pump.

[wildbob]

First delivery of parts!! Awwwww yeah, come to daddy! Jug, forged piston, and head.

[xlint89]

Those aren't cheap parts. Why do you think this is going to blow up?

[wildbob]

Because I'm doing all the work myself and the stroke is a bit ridiculous..

[jmansracerocket]

Awesome wildbob, can't wait to see it done and hear ur results.

[scjeep4.7HO]

Just because you do it yourself didn't mean it will blow. Check your tolerances, torque properly, check for any interference by hand after assembly, make sure the timing is set right

[xlint89]

Right ^^^^^^

take your time and check everything really good before you seal it up. Pretty sure piston skirt to crank shaft needs to be payed attention to with that long of a stroke. (possible touching/machining)

Watch a few how to videos before going into to give you a good idea of what you're going to encounter.

Proper engine break in would be called for as well.

Oh, and you may need to alter things slightly too. Exhaust mounting may change a tad with that much height added to cylinder, and valve cover to cart clearance may change because of it too.

[wildbob]

Yep, the only thing I'm not confident about is the transmission. I haven't seen one video or guide on how the hammerhead/trailmaster gearbox should go together. I've had the motor completely apart before, just not the gearbox. Starting with empty shells let me make sure I have quality bearings/parts throughout the entire motor. The folks at Taida were awesome too. They had me send pics and measurements especially the crank, to make sure everything would work. Luckily, the exhaust port clocking is the same as my other 4V head, so I should be able to move my hammerhead racing exhaust right over.

[jmansracerocket]

with that big of a stroke comes a lot more side wall pressure. With the 62mm bore the side walls are super thin to begin with and me personally would never recommend. xlint I know u have the 62mm bore and ur the only one I know of that hasn't had a problem yet. I personally have talked to a couple of people who have had no luck with the 62mm bore. With the bigger stroker also the high rpm becomes your enemy. Another thing with that size stroker you have to check your bdc clearance to see how far its going into the case. Also will generate more heat. I do wish wildbob the best on it but I cant see it being reliable.

[wildbob]

Yep, it's blowing up for sure..

[xlint89]

Originally Posted by jmansracerocket

with that big of a stroke comes a lot more side wall pressure. With the 62mm bore the side walls are super thin to begin with and me personally would never recommend. xlint I know u have the 62mm bore and ur the only one I know of that hasn't had a problem yet. I personally have talked to a couple of people who have had no luck with the 62mm bore. With the bigger stroker also the high rpm becomes your enemy. Another thing with that size stroker you have to check your bdc clearance to see how far its going into the case. Also will generate more heat. I do wish wildbob the best on it but I cant see it being reliable.

No problem with the 62mm thus far. And we've flogged the Hell out of the thing. It is a good quality piece (NCY nicasil) with the NCY 2.2mm stroke crank in her.

And yes, that 8mm crank will not like high RPM. I'd suggest letting that high torque engine pull a larger sprocket or internal gears. Which is pretty easy to do if your HH is like my Yerf (Howhit) engine.

[ckau]

I do wish wildbob the best on it but I cant see it being reliable:quote
There's always a tradeoff between reliability and performance. Though Wildbob's motor may only last a 10th of the life of a stocker, the fun factor goes off the meter. Everyone who's into gy6s has to do this once.

And yes, that 8mm crank will not like high RPM.:quote
LOL... With those crankshaft balances being what they are, yea it gets pretty crazy when they turn up!

[wildbob]

Yeah, gonna look into putting a little taller gearing into it. I don't know what I can do internally and what I can do externally.

[SYCARMS]

Tiada makes a long rod stroke in 8mm. The difference is that it will come with a longer cylinder so no spacer is needed. The long rod used with the correct piston will not create any side wall pressure. I have the 6mm long rod stroke in mine with a 63mm bore and have yet to have a problem after 5 years. The trick is that with their setup you are not raising the sleeve up out of the case by using a spacer so the piston rides in the bore just like the stock does. Take your time and it will last a good while.

[wildbob]

yup, that's what they set me up with. They were pretty awesome about making sure I measured everything, sent them pics, measured again, talk to their boss, email me back with a package. They seriously told me "measure this, send me a pic of this, measure that, send a pic of this part of the crank case" before they'd even let me order anything. There was a lot of back and forth emails, but it was because they want me to build a monster that I can brag about, and showcase their products. I've got to say I was pretty impressed.

[SYCARMS]

You will be really happy with your build and it will be reliable. I'm going to start handling their parts since I can buy smaller orders and still be competitive. They make the components for the top line scooter companies like KIMCO,Aprilla and like .

[wildbob]

Koso Hi-flow oil pump, magnetic oil drain plugs, engine bolt set, heavy duty starter clutch..

[xlint89]

Don't skimp on the starter. That's going to be a lot more load trying to turn over that engine VS. stock.

I installed larger battery cables to help the starter on mine.

[wildbob]

Yeah,
I have a high output starter on the way, and I made my own wiring harness with thicker gauge wires.

[jmansracerocket]

you ever finish the engine wildbob?

[wildbob]

Not yet, work has been brutal. Taida is making the crank as we speak and will ship with the oil cooler case-half, oil cooler, HO starter motor, and case cutting tool. I still have to order all the bearings for the motor and tranny, as well as the full Dr Pulley kit. I'm also exploring the possibilities with Jin-Lang (they make the trailmaster motors) about seeing if they make a "B" case version of this motor for a future build.

[wildbob]

Got an email from Taiwan today that I should have some stuff on the way!

[wildbob]

Got my new KDU 8200 crank. Here it is (bottom) next to a stock trailmaster crank. Bearing sizes are identical, so hopefully it will work with no problems..

[wildbob]

and the new case cutting tool. Set length of cutting tool, bolt to engine case like a a cylinder, and away you go.

[wildbob]

cooler, cooler case, and hi output starter motor.

[xlint89]

Love when parts show up. It's like Christmas morning as a child.

Is it just me or are the splines different sizes between the cranks?

[wildbob]

You might be right, I'll have to take a look at that. I'm fairly certain that if I need I different pulley, Dr Pulley makes one that will fit. The splines on my old motor got beat to hell for some reason. It was no cake-walk getting the old pulley off, or I'd be re-using it.

[wildbob]

Splines are the same size, but looks like there's about 5mm more spline on the stock shaft, they look to start at the same distance from the center, so hopefully everything will fit ok.

[SYCARMS]

Before you install the crank try your variator on the new crank to make sure it fits and can be tightened.

[wildbob]

Indeed that's what I'm going to do!

[xlint89]

Excellent.......

Looking forward to this thread WB

[SYCARMS]

Just wondering if your new cylinder is taller than the stock and does your build require any shims or is it a direct bolt on.

[wildbob]

it is taller, i think 75mm cylinder height (not sure off the top of my head), so no shims. The sales person at Taida mentioned that shims and spacers aren't a good way to go, so their stroker package has the taller cylinder.

[SYCARMS]

That is good, for you will not have the sidewall pressure as with the normal deck height would. Just keep in mind the piston provided is designed for the long rod stroke. I would suggest ordering a spare rings and piston in case you ever need one. I have been running the 6mm stroke on mine for 6 years now without a hitch turning the motor as high as 9000rpm at times. The only issue I see you having is the taller cylinder and taller head you will not get the seat all the way back without the exhaust burning through it. Hopefully your buggy will have more room back there than my Blade has.

[xlint89]

And exhaust pipe clearances may come into play too. Had to manipulate mine a bit after the longer cyl length. (that was only a 2.2mm gain, but the head may be slightly taller too)

[wildbob]

Got my new Dr Pulley variator and 11g sliders, looks like it will bolt on fine. I don't know what caused the one on my old motor to strip off the splines on itself and the crank it as it was still bolted tight (only $99, but would have been nice to reuse it) so I would have had a complete tear-down in my future anyway. I'll post pics of the old one and crank..

[jmansracerocket]

wildbob, just want to make a suggestion the 11 gram sliders are probably going to be to light of a slider. But hey everyone likes something different.

[wildbob]

Hmmm, I used 11g before, but I'll get a set of 12g and try 'em out

[SYCARMS]

What you had for an engine before and what you will have now is totally different. I run 16gr. rollers in my 150 buggy since my engine can power through the shift range. You may want to wait a bit till you get the engine dialed in, then tune the cvt. The main reason people go to lighter rollers is due to the engine not having the power to move the heavier rollers up the ramp especially when under a big load such as climbing hills. Once the engine has sufficient power to pull the buggy up the hills lighter rollers are not a benefit.

[wildbob]

Good to know, thanks for the heads up!

[jmansracerocket]

don't waste ur money on the 12s, wont be much over the 11s. Finish your build get everything buttoned up put the 11s in since you have them already then go from there with tuning the cvt like tom said.

[xlint89]

I agree. Running 14g sliders in mine with great results. And you're going to have more HP than me for sure.

[wildbob]

Legit advice, thanks guys!

[tkeagle]

Sounds like a nice build. Been wanting to do same with mine. I can have a full one custom built for around $900.00 ready out of box. Wondering what your price tag is for all this? Just the engine part, skipping the CVT and clutches. Busy time of year is coming up for me, so not sure how much time will have to rebuild myself. But if I can save a few hundred $, doing it myself, I'll go that way. I have 2 spare engines I can play with. And from what I understand, is the only danger in that type of build, with that stroke is the RPM range. Any thing over 9000 rpm you getting in a dangerous range. any confirm that?

[SYCARMS]

As stated in past posts I have the 6mm long rod stroke. My power band will cease at about 9200 rpm. For dirt drags that is fine but if on a long stretch you will only be putting the max stress on the engine. I have more than enough power at the bottom rpm range so I will be re-gearing my final drive which will move the power band to a lower rpm range since now most of my driving is on trails and hills. Now my buggy is the early GY6 with external reverse so I have the option of re-gearing the final drive which the internal reverse models don't. I run the stock sprockets on mine so he may have to go with a smaller axle sprocket. That will be determined once he gets it all together using an accurate tachometer.

[wildbob]

So with some spare time on my hands, I decide to do a test bore-out on some spare cases with the Taida case boring tool..While the tool itself seem to work fine, getting the setup correct for the correct cut width was more difficult than I expected. Maybe if I had more machining experience or "knew what I was doing" it would have been more successful, but I think I'll strip and box up the new motor I bought for the build and give Tom at SYC Powersports a call to bore out the motor.

[SYCARMS]

E-mail me some pics of your boring tool tom@sycpowersports.com. I've never used one of those tools and have heard good and bad with the most complaint being that after 2-3 used the cutters dull and are not replaceable. I had another dealer tell me the tool is easy to use but that you have to take your time and is only good for 2-3 bores.

[wildbob]

So I tore down my motor to ship to Tom for a bore out and I noticed it looks like Taida pre-cut my oil cooler case half for the 62mm jug. weird..

[wildbob]

Must...Finish...project..
Work and Life duties haven't allowed me to finish this project yet. Motor ready to be bored. Parts sitting in a bin...

[jmansracerocket]

It's ok wildbob I still haven't finished my hammerhead since last year.

[wildbob]

Update: I've gotten nothing accomplished. Motor is bored, but work/life getting in the way of assembly.

[wildbob]

Yay vacation! Looks like the KDU stroker crank fits so far.. I haven't put the pulleys on yet, but so far, so good.

[xlint89]

Dam... That looks purty.

Don't rush it, take your time and check everything.

And please don't rush the break in either. I ruined a strong motor by doing that on the bike. Never again.....

[wildbob]

getting there..

[jmansracerocket]

looking good wildbob, I see you have the 4 valve head also, going to get tight in the buggy frame / to the back of the seat.

[SYCARMS]

That is going to be a killer motor!!

[wildbob]

And just remembered that I loaned out my torque wrenches and they got stolen out of my buddies car with all of his other tools. I guess I'm on hold again until I can get replacements. I have a crappy electronic one, but I'd rather hold out for the real deal.

[jmansracerocket]

Originally Posted by wildbob

And just remembered that I loaned out my torque wrenches and they got stolen out of my buddies car with all of his other tools. I guess I'm on hold again until I can get replacements. I have a crappy electronic one, but I'd rather hold out for the real deal.

Thats why i dont loan out my tools. I spend good money on tools and friends just expect me to lend them out, i say no.

[xlint89]

Does your auto parts stores loan out tools? Might be able to get one and keep on going with the build.

[wildbob]

It's all good, I ended up hanging out with some old army buddies last night, got all banged up, and will be spending today on the couch groaning and watching football.

[wildbob]

UPDATE: Still haven't gotten this thang finished. It's all together but the heads, but my work table is buried behind so much stuff that I can't get to it. If Sycarms is still doing motors, I'll see if he wants to finish it off. I'm a failure.

[OLDKID]

... ... ... Oh , The Shame Of It All .....
At this rate , at least , it will last a long time ....

[SYCARMS]

Originally Posted by OLDKID

... ... ... Oh , The Shame Of It All .....
At this rate , at least , it will last a long time ....

Yea but it's no fun unless you can drive it like you stole it.
Give me a call Bob, I e-mailed you my # .

[wildbob]

Motor together, just cutting the cooling shroud to fit around heads.

[wildbob]

Originally Posted by SYCARMS

Yea but it's no fun unless you can drive it like you stole it.
Give me a call Bob, I e-mailed you my # .

Thanks for the heads-up on the cylinder studs, they were infact upsidedown... The motor is together, valves timed, spins nicely. Hoping i didn't forget a washer somewhere in the CVT. Got to put shifter assembly and mounting brackets back on, attach to the chassis, and jet it.. Got some tank foam blocks to put in the tank to keep the gas from sloshing as it would leak from the cap when I hit the bumps too hard.

[gobs]

Good Luck and can't wait to see some video of this thing on the trails.
Thanks and good luck

[wildbob]

Yeah, it's either gonna rip or explode. I wish there was more gearing options because the motor isn't gonna like high RPM's. Once I get it jetted I'll see where I'm at gear wise. After I get it in the chassis I've got to figure out where I'm mounting the oil cooler I'm gonna run it on 110 leaded racing fuel (that smell!)

[gobs]

Love the smell of race fuel, reminds me of New England Dragway.

[neo71665]

Originally Posted by wildbob

Got some tank foam blocks to put in the tank to keep the gas from sloshing as it would leak from the cap when I hit the bumps too hard.

Be careful with those anti-slosh foam blocks. I've seen way too many turn to goo and clog up fuel systems. What I used to run was the plastic golf balls with all the holes in them. You can fill a tank through the filler neck, they stop the sloshing, and they don't seem to get eat up by gas. Just don't pack them in so tight you collapse them, they have to stay open so they fill with fuel.

[wildbob]

I've had the same foam in my Ducati for 10 years, haven't melted yet

[wildbob]

Now if I can just remember where I put all those bits to the chain tension adjuster...

[wildbob]

Aaaaaand I forgot to put an engine mount bushing in.. Looks like I've got to pull the cover over the stator off to get that bushing in..

[SYCARMS]

Lookin good, didn't you go with the stroked crank?

[wildbob]

I did!!

[SYCARMS]

You will definitely notice the power increase and should have no problem hitting 50mph.

[wildbob]

I'll post the parts invoice when I'm done. I also bought a little bit bigger front sprocket, but I'll have to do some testing before I put that in.. Also, I'm ordering one of JD's throttle conversion gizmos because my homemade converted cable to use the mikuni carb is a problem waiting to happen.

[wildbob]

LOL, tore the crankcase gasket pulling the case apart to install the engine mount bushing. Ah well, JD's throttle kit is on the way anyway, another week won't kill me..

[wildbob]

Almost done!! She's still full of twigs and crap from the last time I blasted through some unsuspecting bushes..

Engine mounted, exhaust and carb attached. Just gotta double check the wiring, add oil/gas and the following:

*Decide on location to mount the oil cooler. (currently tie-wrapped to the frame forward of the engine)

* Install JD's Basic Slide kit.

*Decide on output sprocket. Stock is 14T, but I have a 15T, 16T, and 17T to choose from.

*New battery for the TrailTec Vapor.

[SYCARMS]

Run with the stock setup first so you can tell the difference in the engine than go from there.

[wildbob]

If anyone knows better please chime in.. I'm thinking of spinning the engine a bit with the starter to sort of "charge" the oil cooler, check levels, repeat.. I'm just not sure if the extra length of the oil lines will leave the motor dry before the lines fill up.

[SYCARMS]

If assembly lube was not used on cam lobes just squirt some oil on rockers and cam that will be enough until the pump moves the oil up to the head. That pump will produce about 35PSI so it won't take long at all to pump oil to the top. If for some reason you did not oil the pump before install turn over by hand so it could prime.

[wildbob]

Yeah, I used assembly lube and gave the rockers a healthy coating of oil. I'm just getting the jitters as "D-Day" approaches. I'm not sure how much more strong the Koso high-flow pump is over the stock one. The stock pump seemed to push the oil pretty good, I know I'll never spin the motor with the valve cover off again.

[SYCARMS]

Ha Ha, been there done that. The KOSO pump will be a higher volume pump and will work well. Run some break in time so the rings can seat fully I'd say 2 hours moderately.

[wildbob]

It runs!!! It ruuuuuuuuuuuuuns!!!!

[SYCARMS]

With your knowledge and the best parts I had no doubt's. But it is a damn good feeling when it fires up and sounds and runs great. That Mikuni when dialed in your gonna have one mean buggy. Keep us updated.

[JERSEYDEVIL]

Nice job buddy

[wildbob]

Thanks guys! I've just got to get the electrical box buttoned up and adjust the F-N-R shifter, drill some holes for JerseyDevils slide kit and it'll be ready for some testing.

[wildbob]

Shifter adjusted.. Forward and backwards achieved. Needs some air in those tires. JerseyDevils slide kit is the bomb!!

[JERSEYDEVIL]

that's awesome, i'm glad you like it. looking forward to some feedback!

[wildbob]

I hate the electrical box on this thing.. I'm resisting the urge to make a nicer one because I need to get out riding it.. Got some roll bar mounts for the oil cooler on the way. Haven't given it a spin around yet, but i think it's going to rip. It's a bit louder too..

[wildbob]

I also got a universal fan kit from trailtech that will mount to the oil cooler (once I have mounts to permanently attach the cooler.) It says it uses 14W which should be fine. I'll set it to kick on at about 250 degrees.

[wildbob]

reduced pilot jet to a 17.5.. No more bog at low throttle. took a quick rip up and down the street keeping it at a sedate pace while the motor breaks in. This thing feels like it's going to tear it up. The universal fan kit from trailtech is a bit big for the Taida oil cooler, I've made some temporary brackets for it, but I can't decide on a location I like for it, and might switch to a bigger B&M trans cooler that I've got sitting in a box. The fan doesn't even blip the voltmeter when it kicks on, which is nice. If it ever stops raining, I'll get her out on the trails this week to put her through some paces, but I've pretty much got to say this project is a wrap!!

[SYCARMS]

You know you can also run these in the rain.

[wildbob]

Good point.

[wildbob]

Haven't beat on it yet, but so far it has failed to explode, minus the issue with me not torquing down the variator.