Dax Balanced lower...?

"Dan from what Ive seen and have heard, anything fred makes or sells is worth the price and does exactly what he sez it does "

Yeah he has a good rep for sure. Where does the bleeding of funds end lol. I still need a front brake system, maybe drum I dunno, either the puch head which I love because of the price or a fred head, need an intake, exhaust, carb (RT from dax) so on and so on lol.
 
Dan, all I'm doing is pointing you in a good direction on some things just like it has been done for me here in the past, there is a lot I dont know and I am not an expert on these engines, but what I do know is what I have done and proven to work on my engines so these are things I share freely, I'm glad that I can be of some help to ya and before it's all said and done I'm sure there will be several other that will continue to ring in here with advice and ideas.

I just want to see you with a good strong running engine when you're done that will cause yo to get a mouth full of bugs...LOL! thats what happens when you're so happy that you just smile big the entire ride because you're so happy with how it runs when you have all the bugs out.

Map
reddd
 
mapbike said:
Dan, all I'm doing is pointing you in a good direction on some things just like it has been done for me here in the past, there is a lot I dont know and I am not an expert on these engines, but what I do know is what I have done and proven to work on my engines so these are things I share freely, I'm glad that I can be of some help to ya and before it's all said and done I'm sure there will be several other that will continue to ring in here with advice and ideas.

I just want to see you with a good strong running engine when you're done that will cause yo to get a mouth full of bugs...LOL! thats what happens when you're so happy that you just smile big the entire ride because you're so happy with how it runs when you have all the bugs out.

Map
reddd
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haha to true! I always rode my crotch rocket with a full face helmet but I promised my wife years ago to leave those things alone, I don't have a lot of self restraint lol. But, last night I was hit by my first bug :)

Dan.
 
I found a grasshopper in my shirt pocket yesterday after a several mile ride, it was a big one and it was dead so I guess it must have hit me pretty hard but I dont remember feeling it hit me.....LOL!

Map
reddd
 
That's just gross lol.

Should be ordering that head tomorrow :) need to talk with duane first and cancel the order for the head he didn't send me.
 
Danschutz said:
That's just gross lol.

Should be ordering that head tomorrow :) need to talk with duane first and cancel the order for the head he didn't send me.
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Sounds like a plan there Dan.......

Yep no need for the dax head if you go with the Puch.

Now the Puch heads need the stud holes drilled out for the M8 studs and the best socket I have found for getting into the narrow recess where the studs come through the head is a 1/4" drive deep socket, most of them are fairly thin walled and that is a must for getting the nuts on the studs and tight, get you some good regular M8 nuts, the ones I picked up are for using a 13mm socket, just another tid bit of info for ya on dealing with a Puch head install.

Map
reddd
 
Tyler6357 said:
I have a Dax Lower end F-80. I originally replaced by stock kit engine with a cheap BGF engine. The BGF engine seemed to fall apart before I even got to 1000 miles on it. The crank got bent and just kept blowing the seal at the magneto so I ordered a Dax type "D" bottom end F-80 and used the top end from the BGF engine that was still good. All I can say is that it has a noticeable increase in power than the first engine I got with my kit as well as the BGF motor I had. I should say that the BGF motor had troubles with air leaks from the start, the head stud threads were just so poorly made. I tried to fix them with a die/cast kit until the bottom end crank got bent somehow. I think I just got a lemon from BGF. But I am very happy now with the Dax bottom end. I've just finished breaking it in. My Mountain bike has much more power and torque than it ever did. I can get up to 24mph at about half throttle with my SBP Expansion Pipe set back a bit and a Delorto Clone Carb.
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I need to update my last post here. Today, my motor seized. It was running great as it never seemed to lose any power since I got it. It seemed to break in well and I've been using a 32x1 mix of Castor 927 with gas (E10). I was riding along in the power band at 25mph up a moderate grade and it bogged down and died. When I tried to restart it wouldn't move. I peddled the 1/2 mile uphill to get home. Took off the BGF head and cylinder. The cylinder was pretty scraped up but my bottom end still seems to crank ok. The piston and head are black. Spark plug seemed kinda gray. I guess putting that BGF upper end on it wasn't such a great idea after all but it ran awesome for 3+ months (I ride about 1-2 times a week). I still think the bottom end is good but not quite sure. I wonder if it's still balanced after an incident like this??? Should I get the top end from Dax? or should I get a completely new engine? or maybe I should just get both so I am well prepared for the next break down, haha. I'm still pretty sold on these balanced bottom ends in spite of this happening, maybe the BGF crap couldn't handle it or something, The thing was running the best I've ever seen before this. Do you guys think this bottom end is worth saving??
 
Danschutz said:
Thank you Sir!
Just ordered the HEAD!

Dan.
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if you use the 12mm acorn nuts that come with Dax's top end you will be fine a reg 12mm socket will fit just fine. also you may want to order a 2nd head gasket it will lower the compression some but the first puch head I used I had to have 2 gaskets because the piston hit the head. the one I put on today seems fine with 1 gasket but Im not 100% sure yet Ill take it for a good long ride tomorrow and decide then if I need to get a 2nd gasket or not.
 
Tyler6357 said:
I need to update my last post here. Today, my motor seized. It was running great as it never seemed to lose any power since I got it. It seemed to break in well and I've been using a 32x1 mix of Castor 927 with gas (E10). I was riding along in the power band at 25mph up a moderate grade and it bogged down and died. When I tried to restart it wouldn't move. I peddled the 1/2 mile uphill to get home. Took off the BGF head and cylinder. The cylinder was pretty scraped up but my bottom end still seems to crank ok. The piston and head are black. Spark plug seemed kinda gray. I guess putting that BGF upper end on it wasn't such a great idea after all but it ran awesome for 3+ months (I ride about 1-2 times a week). I still think the bottom end is good but not quite sure. I wonder if it's still balanced after an incident like this??? Should I get the top end from Dax? or should I get a completely new engine? or maybe I should just get both so I am well prepared for the next break down, haha. I'm still pretty sold on these balanced bottom ends in spite of this happening, maybe the BGF crap couldn't handle it or something, The thing was running the best I've ever seen before this. Do you guys think this bottom end is worth saving??
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Sorry to hear about your troubles, one thing I can say for certain is that most likely the BGF parts had nothing in themselves to do with the failure, I have been running uppers and entire engines I bough from them for several years now, as seized piston and jug is a sign of improper lubrication or improper carb tune causing extreme lean mix which will cause a serious overheating problem or a serious air leak that caused a bad lean run condition.

If the lower seems to be in good shape and there isn't any debris from the upper failure in the crank case I say pop another jusg piston rings and wrist pin bearing on it get you some Opti2 oil for your mix and enjoy a beter running engine.

Just get a new jug and piston off a vendor on ebay thats as cheap as you can find and order a high quality needle bearing for bearing direct and you should be back on busines.

Best wishes to ya.

Map
.wee.
 
Scott.D.Lang said:
if you use the 12mm acorn nuts that come with Dax's top end you will be fine a reg 12mm socket will fit just fine. also you may want to order a 2nd head gasket it will lower the compression some but the first puch head I used I had to have 2 gaskets because the piston hit the head. the one I put on today seems fine with 1 gasket but Im not 100% sure yet Ill take it for a good long ride tomorrow and decide then if I need to get a 2nd gasket or not.
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Thanks.
I think Im going to get the SBP stud set and just take care of a possible issue before it happens lol. Map said in a earlier post that the puch 50cc head needs 2 gaskets but the 70cc does not. I ordered the 70cc head.

Usually Im chomping at the bit to get stuff done but Winter will set in for the next 6-8 months and I can do everything nice and precise :)
 
mapbike said:
Sorry to hear about your troubles, one thing I can say for certain is that most likely the BGF parts had nothing in themselves to do with the failure, I have been running uppers and entire engines I bough from them for several years now, as seized piston and jug is a sign of improper lubrication or improper carb tune causing extreme lean mix which will cause a serious overheating problem or a serious air leak that caused a bad lean run condition.

If the lower seems to be in good shape and there isn't any debris from the upper failure in the crank case I say pop another jusg piston rings and wrist pin bearing on it get you some Opti2 oil for your mix and enjoy a beter running engine.

Just get a new jug and piston off a vendor on ebay thats as cheap as you can find and order a high quality needle bearing for bearing direct and you should be back on busines.

Best wishes to ya.

Map
.wee.
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It's interesting that you mention improper carb tuning. I'm running a Dax RT carb which is really just a Delorto clone. It came with equipped with a 70 jet and also came with 5 other jets (60,65,70,75,80). The 70 was way too rich to the point of heavy bogging so I put on the 65 and it totally came to life. It seemed to be riding good while I was breaking it in and afterwards but about 2 weeks ago it seemed to be losing power like it wasn't getting enough gas. I took off the carb and blew air through it and actually heard something spit out. I put it back on and the problem was solved but a few rides later the same thing happened again. This time I took the carb apart and cleaned it with spray. I also drained the tank and sprayed it out with water and let it completely dry out. A week later it seized. You have got me wondering if the carb had something to do with causing this. It was definitely running hot before it seized. Maybe the 65 jet is too lean after it is fully broken in? Maybe I could try the 70 again or switch back to the NT carb. Will it all be different when I put on the new top end and will I need to completely re-jet? Do you know if I can get jet sizes between 65 and 70? Would you recommend trying a different jet to keep from blowing another cylinder? I'm still a bit of a rookie on tuning the carb and any tips are highly appreciated!!
brnot
 
Tyler, I'm new to this hobby but have fooled around with 2 stroke dirt bikes. I'm using that same carb and in the process of fine tuning for maximum performance sometimes you need to silver solder the jet and then drill a new hole. It can be a head scratching ordeal but take notes and precise measurements and you'll find yourself acting like a mad scientist lol.

I'm worried when you used water to clean out your tank. Perhaps if you got in there real good with a air hose afterwards you might be ok but water can find ways to settle in and stay put, it doesn't take much. Next time finish the clean up with some carb cleaner or the like. It won't hurt anything and drys fast. I'm not saying that's what happened but it is a concern.

Dan.
 
Danschutz said:
Tyler, I'm new to this hobby but have fooled around with 2 stroke dirt bikes. I'm using that same carb and in the process of fine tuning for maximum performance sometimes you need to silver solder the jet and then drill a new hole. It can be a head scratching ordeal but take notes and precise measurements and you'll find yourself acting like a mad scientist lol.

I'm worried when you used water to clean out your tank. Perhaps if you got in there real good with a air hose afterwards you might be ok but water can find ways to settle in and stay put, it doesn't take much. Next time finish the clean up with some carb cleaner or the like. It won't hurt anything and drys fast. I'm not saying that's what happened but it is a concern.

Dan.
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I never thought of drilling the jet out to make it more rich, maybe I should try that, hmmmmmmm. I was wondering if regular Delorto jets will fit this clone and if you can buy them in more precise measurements than offered by Dax. I'm mostly wondering if the engine seized because it was running too lean and too hot and how I can fix that before I blow another top end. I believe the bottom end is still perfectly fine, well, I hope it is anyhow. The top end isn't really in that bad of shape either, the rings didn't break or anything, the piston isn't all thrashed up or anything like that, the cylinder has some scratches though and the head has some slight shredding around the edge of the seal, the head gasket is blown.

I guess I should have said that I didn't just use water to clean the tank. I did spray water in it and let it dry for over 48 hours with the cap off but also flushed it out it with straight gas before I put it back on. I guess I shouldn't have used the hose but I wanted to give it a high pressure spray. You are right though, it was a bad idea, however, I don't think that caused it to seize. It was running hot so it probably was jetted too lean, the more I think about it the more I believe this.
 
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Danschutz said:
Yeah it sounds like it got toasty. I have a leftover infrared temp gun from my autocross days to check tire temps and now use it to check the temp of my motor after a ride. I just googled one and for under 25 bucks you can grab one up. They come in VERY handy with these little finicky gals.

http://www.amazon.com/Temperature-Infrared-Thermometer-Laser-Sight/dp/B002YE3FS4

Dan.
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The RT carb is a good one, pirate cycles and treatland.tv both have the dellorto jets in one or two size increments

I run the RT carb on a stock BGF Engine with a sbp expansion exhaust and the shorty billet intake and it runs perfect with the #70 jet, im in central Texas at 1240ft elevation.

I typically solder and drill my jets with wire gauge bits until I get the plug color im looking for.

It does sound like a lean condition may be what caused your failure.

Map
.wee.
 
Dan
Sweet. that's really handy to have. Tell me, what readings do you usually get off your engine with that thing after a long ride? I live near mountains and hills, it really has to work to get me home up the hill. I was thinking of getting a higher tooth rear sprocket just to make it easier but I hate to sacrifice my speed on the flats!xct2
 
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