attempt #3

[lambofgod121980]

Ok so I have ruined 2 engines already. The first one I bought with the kit off ebay from BGF and it was a total turd. Lasted bout 2 hours before throwing bearings under the clutch and never running again. The second one I was truly happy with and got that one from dax. Ruined that one due to my inability to just leave sh!t alone and stripped out head studs and just about any other stud/nut/bolt on the engine. Then in an attempt to just get me through I tried jb weld to fix it and managed to jb weld the jug to the case and am just tired of messing with it. So totally my fault and the motor was great till I broke it. I am not discoraged in the least so I am going for a third engine.
My question is where do you get your engines and what preinstall tips do you recomend. Loctite is not an option as that's what started this whole mess on dax motor. I am willing to spend a decent chunk of cash for an ht motor if its worth it. And I don't think I'm ready for a morini (think that's how its spelled) motor as I just can't seem to leave things alone.
The only mods I will be doing are already done and won't be messing with the acual engine itself except maybe swapping out the head for a slant head if it doesn't already have one for cleance issues. Ill be useing and offset intake and deltoro clone carb from dax ( love this carb, not only does it look killer but solve all four stroking issues I was having before I kulled the motor) and a ported exhaust.
Thanks
Death metal mike from splendora, TX

 

[Bikeguy Joe]

Read this-
http://motorbicycling.com/showthread.php?t=354

The only other advice I can offer is "If it ain't broke, and you mess with it long enough, it will be.

No one ever takes that advice though.

 

[lambofgod121980]

Thanks was exactly what I was looking for \m/ >.< \m/

 

[wheelbender6]

Sounds like you are a go-getter and overdoing it a bit. At some point you will develop the touch that tells you when a bolt is tight enough. A torque wrench helps but it is no silver bullet.
I would stick with chinese motors until you develop that sense. I don't think a higher quality engine is the real answer.

 

[lambofgod121980]

Yeah I like to tweak and was having problem with four stroking so I kept taking things off and put them back then I felt air leak on cylinder head and tried to fix that and now I've broken off intake parts trying to fix a air leak so I don't wanna waste a bunch of skrilla on a super nice motor just to junk it right off the bat. I am not at all discouraged tho and am finding messing with these HT engines a ridiculous amount of fun \m/ >.< \m/

 

[lambofgod121980]

Update - went back with thatsdax - can't beat his customer service and willingness to answer any questions I had. He also dug the feedback I gave him \m/ can't go wrong with awesome.
I also purchased a torque wrench so as not to have same issues as last time.
Motor is in the mail and will continue to post updates \m/ >.< \m/

 

[nightcruiser]

I never bought a DAX kit, but assuming they are a standard china kit, I would buy a stud upgrade kit and build it up from the start with better studs. All the studs that come from China seem to be pretty bogus and fail sooner or later. Once they fail you have to deal with getting them out and whatever mess that creates, not fun.
I have a heavy hand tightening things up too, which can cause problems with these motors easily. So I started using a click style torque wrench when tightening down most everything. It's not much larger than a regular socket wrench, so why not use it, it keeps me in check and has helped me get a better idea how much torque I've been applying. Those big old needle style torque wrenches are pretty much useless cause you can't fit them where you need them and if you can you cant read the needle. With the click style you just dial the torque on the handle and when it clicks you know you hit it! Easy as pie!
On the loctite, I understand your position after your experience, but I'm thinking if you had better studs to start with it might not have caused issues? Without loctite everything seemed to be coming loose constantly for me. When I rebuilt over the winter I put in a stud kit from SickBikeParts.com with red loctite where the studs go in the block and cylinder, and blue loctite when I installed the nuts on the head, intake and exhaust. So far everything has been holding solid, no constant torquing this year for me! I kinda get the feeling that the constant re-torquing of the cheap nuts on cheap studs is what makes them fail, but if you loctite crappy studs in your screwed to! (as was your experience I guess)
Best thing is to use quality studs and nuts along with loctite IMHO...

 

[lambofgod121980]

I never bought a DAX kit, but assuming they are a standard china kit, I would buy a stud upgrade kit and build it up from the start with better studs. All the studs that come from China seem to be pretty bogus and fail sooner or later. Once they fail you have to deal with getting them out and whatever mess that creates, not fun.
I have a heavy hand tightening things up too, which can cause problems with these motors easily. So I started using a click style torque wrench when tightening down most everything. It's not much larger than a regular socket wrench, so why not use it, it keeps me in check and has helped me get a better gage on how much torque I've been applying. Those big old needle style torque wrenches are pretty much useless cause you can't fit them where you need them and if you can you cant read the needle. With the click style you just dial the torque on the handle and when it clicks you know you hit it! Easy as pie!
On the loctite, I understand your position after your experience, but I'm thinking if you had better studs to start with it might not have caused issues? Without loctite everything seemed to be coming loose constantly for me. When I rebuilt over the winter I put in a stud kit from SickBikeParts.com with red loctite where the studs go in the block and cylinder, and blue loctite when I installed the nuts on the head, intake and exhaust. So far everything has been holding solid, no constant torquing this year for me! I kinda get the feeling that the constant re-torquing of the cheap nuts on cheap studs is what makes them fail, but if you loctite crappy studs in your screwed to! (as was your experience I guess)

Best thing is to use quality studs and nuts along with loctite IMHO...

- the dax motor is usa built with quality hardware factory from what duane tells me over the phone. That being said I stripped the case and broke the studs. I have deff learned my lesson and invested in the click style torque wrench. Was a cheap 20 dollar investment and is exactly what I needed (in lbs).this build will hopefully be the last for this bike \m/

 

[nightcruiser]

- the dax motor is usa built with quality hardware factory from what duane tells me over the phone. That being said I stripped the case and broke the studs. I have deff learned my lesson and invested in the click style torque wrench. Was a cheap 20 dollar investment and is exactly what I needed (in lbs).this build will hopefully be the last for this bike \m/

To my knowledge there aren't any 2-stroke HT motors or kits made in the usa. I am wondering if they replace the Chinese hardware on a china kit? I'm kinda confused about how that works?

 

[lambofgod121980]

To my knowledge there aren't any 2-stroke HT motors or kits made in the usa. I am wondering if they replace the Chinese hardware on a china kit? I'm kinda confused about how that works?

I was under the impression that there weren't any usa made engines either. At the very least duane swaps out the hardware. When his motor and the one I got from bgf from ebay, are set side by side, there is no comparison. The dax motor is all around better. Casting is different and trimmed up, the head is thicker, more sturdy looking on the dax motor and not a cheap bolt or stud on the whole thing. The bgf motor looks like it was just poured and slapped together, most of the screws and studs stripped the second a screwdriver or socket touched them. Not to mention the fact that it dropped bearings under the clutch in a matter of 2 miles. And the extra cash I paid for the black paintjob was a joke, as if the motor is looked at from eye level there is paint missing everywhere - looked great if you looking strait down on the head from the top. And was also missing head gasket when it arrived ( I made one from a monster can).
And thus has been my experience with these ht engines so far, and why I went back with the dax engine. I was just curious as to what else was out there when I originally posted this thread but ultimately went back with duane and gradys motor. - and also their customer service is better than exellent, they are always willing to talk to me on the phone and answer any questions I might have and even called me to make sure I recived my package on time. And they seem to dig the feedback I give them \m/

 

[Al.Fisherman]

Here....read this.. https://docs.google.com/document/d/1GcesQihc7-mm3hJGf7UPiqOaRXZ8ekUT99QUZq2qXXE/edit

 

[lambofgod121980]

Great info AL saw a few things I didn't know. \m/

 

[Kickstart70]

On this note, what engines are the absolutely top in quality, and are still made today? It seems like most people are saying that all the good engines are those that stopped production long ago.

This is partly why I am strongly considering a self-build from a Stihl chainsaw.

 

[donphantasmo]

I have to say, man. I'm sorry about your luck. I got my first engine off of Piston bikes, and have had no problem with it, at all. I have about 9 months of riding it at least 2x per week. Here is what I did.

I looked at the engine all over before I installed it. I'm a Jet mechanic by trade, so I know when something doesn't look right. I took off the head, and made sure the surfaces were even. I did that by getting a big sheet of plexy-glass, and puttine 1200 grit sand paper on it. I then went in a circular motion with some water and sanded down both mating surfaces of the head. I was careful not to take off too much, because that directly impacts the compression ratio. But that's good, though.
I then took the top nuts and replaces them with new ones. I got two nuts to put on top, rather then the cylinder head nut they give you in the kit. The reason I do that is because the nut can bottom out (rather really top out). That means the stud can be stopped by the top of the nut, and still torque down correctly. That'll give you improper seating of the cylinder head to the cylinder itself, and you'd loose power (and compression).

Also, I changed the lead to the CDI. I went to a small engine repair shop and got a 8.8mm spark plug wire, and got an NGK sparkplug.

I also had a good quality oil. I use Amsoil. I used it 32:1 with the 89 fuel I have. I would start the bike, let it idle till it got hot, then I'd ride it down the street, making sure my RPMs would stay nice and low. I did that a few times.
I then got higher and higher RPMs untill I felt the engine was broken in. I constantly checked the spark plug color to make sure I wasn't too rich/lean.

Also, I make sure to ride it like a bicycle, not a motorcycle. I don't ride in the rain, I don't need to break the land speed record for a single cylinder motorized bike. I know what I got (a hobby) and not a 100% reliable mode of transportation. So, I ride it accordingly.

I hope this works for you, man. Let me know if you need anything. I got my kit for 149 (it was a last year closeout). It still runs great...

Chears.

 

[lambofgod121980]

Thanks mr. donphantasmo
Was some great advice in your post. Tom has also recommended lapping the head aswell and that was only thing different I've done this go...
Currently I have purchased a 80cc frome duane and grady and everything I have done to my bike is as follows -
-Milled the head with 320 grit sand paper ( worked great)
-Port matched the exhaust
-Port matched the intake and also using an offset intake so I can run a different carb
-swapped nt for dax rt carb
-all hardware has been swapped by dax to sweet high quality stuff
-swapped cdi wire for 8mm replacement
-using ngk spark plug

I also bought a new in lb torque wrench. I read somewhere that I was good to 120 in lbs. No loctite on this engine. I am running lucas 2 stroke oil and cheapest gas. So far so good put a couple miles on the bike today and seems to be running great today. I'm going to check the tourqe on head nuts tomorrw just to be sure they are snug and make sure I got no leaks and then solder up my kill switch and such, then take it out.

I'm using the bike to cruise to the convienence store few times a week and ride a few trails through the woods now and again. Riding in the woods is a little abusive and I'm trying to achive decent hill climb and nice cruise speed bout 15-20 cruise speed. I won't be getting any kind of shift kit any time soon but may do that on another bike build. I'm not a giant guy at 200 lbs but I realize that's pretty heavy. The bike is super heavy too, I wanted to make sure the bike would take some abuse.
And almost forgot - the bike is a 24 inch bike with a 20 in wheel in the back and front is original 24 inch wheel. I was hoping this would give me decent bottom end. Bike has never seen higher than 26 mph on flat land. Uphill on the street tops at about 15 or so. Ion rough terrain I take it a little easy and only work it hard when I'm climbing steep grades. Its still bogs pretty good on medium size hills. I might get a bigger back sproket. Running 40 tooth now. I thought I might try a 44 tooth and see if it even makes a difference.

 

[lambofgod121980]

Lmao - I'm about to tap out
Engine #3 is a dud I'm extremely sorry to say. Recived it yesterday mounted it up and rode it a mile or so. Ran pretty decent. I got off work today and went to do my pre ride check and once again head stud is stripped out. I just don't know what happened, I used torque wrench and sugged each one up to 120 in lbs. *sigh*

 

[nightcruiser]

Lmao - I'm about to tap out
Engine #3 is a dud I'm extremely sorry to say. Recived it yesterday mounted it up and rode it a mile or so. Ran pretty decent. I got off work today and went to do my pre ride check and once again head stud is stripped out. I just don't know what happened, I used torque wrench and sugged each one up to 120 in lbs. *sigh*

What is happening to the stud, is the whole stud turning or the nut turning with the stud staying in place?
Do you have acorn nuts or regular nuts on the studs? Sometimes the acorn nuts can bottom out and start turning the stud into the motor rather than the nut on the stud and that may head you toward troubles. The holes in the block are tapped to varied depth, sometimes not deep enough and the acorn nuts bottom out too soon. The acorn nuts have a nice look, but I wont use them for the above reason.
I never got a motor from DAX and dont know what hardware exactly you got, but you said it was upgraded from stock, so you might want to contact them and see what they have to say about your problem.

 

[lambofgod121980]

It came from dax with shouldered hex nuts and acorns on top. I removed the acorns before any kind of tourquing and the stud is deffinatly stripped the nut and stud both turn and its loose enough that you can spin it by hand. I have made sure its all the way down and it never gets tight - I've called dax and am waiting for return call cuz its late and I'm sure his shops already closed for the day. I'm sure he will be more than willing to make it right as so far my personal experience with his customer service has be beyond excellent and will post an update when I have something new to share \m/
Just super frustrated cuz I was looking to put some miles on today and am off tomorrow. At best I can hope to be back on the street in a week or two. I have spent way more time working on my bike than riding and have sunk bout 600 bucks in my bike since the begining. Kinda seems like its not worth it....

 

[GoldenSprocket]

Lmao - I'm about to tap out
Engine #3 is a dud I'm extremely sorry to say. Recived it yesterday mounted it up and rode it a mile or so. Ran pretty decent. I got off work today and went to do my pre ride check and once again head stud is stripped out. I just don't know what happened, I used torque wrench and sugged each one up to 120 in lbs. *sigh*

Wow... That is a horrible run of luck!

I'm surprised that that you are having issues stripping the studs if you are using a torque wrench... Especially if the studs and hardware are of higher quality. Is the torque wrench for "inch pounds" or "foot pounds"? Is there a way to check and see if the torque wrench is calibrated correctly? Are stopping tightening after the first "click"?

I learned the hard way (In a similar/expensive fashion) that there is a HUGE difference in in/lb versus ft/lb...

I hope this doesn't keep you from trying again! If you stripped the studs (not the stud holes) you might be able to get by with a new stud kit...

Best of luck...

 

[lambofgod121980]

Wow... That is a horrible run of luck!

I'm surprised that that you are having issues stripping the studs if you are using a torque wrench... Especially if the studs and hardware are of higher quality. Is the torque wrench for "inch pounds" or "foot pounds"? Is there a way to check and see if the torque wrench is calibrated correctly? Are stopping tightening after the first "click"?

I learned the hard way (In a similar/expensive fashion) that there is a HUGE difference in in/lb versus ft/lb...

I hope this doesn't keep you from trying again! If you stripped the studs (not the stud holes) you might be able to get by with a new stud kit...

Best of luck...

100% sure its in lbs and it never clicked just spun. Got the stud out of the engine and looks like stud isn't stripped but hole it threads into is. Looks like someone jb welded it in to begin with. Stud has jb weld caked in threads and a chunk still stuck to the bottom. Im thinking it may need to be drilled and helicoiled or timecert ect to fix it. I'm not thrilled about having to remove the jug (means I have to take intake and exhaust off as well as remove the engine from my bike again X(..... ) to get to the one hole. Means new gaskets aswell. I'm sick at all the cash I have sunk into it already. Its not even a nice bike, you could say its a rat bike