Crank finally snapped

[Ride1Rob]

Well guys/gals, it finally did it! During moto #1 on lap 3 last nite she came to a sliding halt. Once I saw the tires lock up I knew what it was but being the parent that I am I trotted over to see if perhaps maybe I could get him restarted. Once I got to him I could see a lil oil dripping from the flywheel cover and I knew for sure. Tried to turn the kick over by hand and it wouldn't budge. Another parent was very generous and let Jam ride his boys backup bike for moto #2 so at least he could race. That's just AWESOME :muscle: !!!

Since I was pretty sure on what the problem was I pulled the flywheel coveroff a few minutes ago and it was indeed the crank. Snapped completely off and began to grind against his magneto. The way these bikes have been having crank issues I am suprised that it lasted as long as it did (1yr 7mos). And this is not even close to being a stock Typhoon.

With the parent allowing Jam to ride his sons backup DRR I figured this would be a perfect opportunity for us to compare the difference in the two bikes. When he first got on it and test rode he said the bike felt better than his and he wanted me to buy it right then on the spot :ermm: . I took him to the peewee track to let him get alil comfortable with it and he fell in love with it even more. At this point I was thinking go ahead and get him a DRR and sale the Typhoon. Before the race started I told him to be careful and ride within himself and have fun. He finished quite a ways off as he was on the Typhoon but that was expected because of the change.

After the race I asked him to give me his evaluation. He said that his Typhoon was faster and he wanted to keep it. I picked him for more information and he said out of the corners the Typhoon had alot more power. This was a very big relief to me as I was expecting for my pocket to take a nice hit making the swap. Now all I have to do is put a stonger crank in and maybe check/change a couple of other things while the motor is torn apart. These Typhoons (once built) can make some awsome power. With that being said it's time for me to get to work on this motor. I have two weeks before his next race :uhoh: .

Here are the pics of the snapped crank.

http://img82.imageshack.us/img82/5878/1001038.jpg (http://www.imagehosting.com/)

http://img523.imageshack.us/img523/1976/1001039w.jpg (http://www.imagehosting.com/)

http://img164.imageshack.us/img164/3032/1001041.jpg (http://www.imagehosting.com/)

[ccdhowell]

Who makes a stronger crank? Can you use one from a Honda engine?

Daughter races a Typhoon XC, it's just a matter of time before I'm in your shoes I reckon.

[leager-n-ky]

Thats weird, all three of ours broke off on the clutch side, right where that silly ***** second clutch is. Let us know what you find out about the cranks.

[Ride1Rob]

I had heard that GPX makes strong cranks. But I've been told that GPX and Jailing are the same. I'm confused on that one but will have some answers soon. I'm not sure about the honda crank dropping directly in. Not considering doing too many changes as the bike was running really well. I'll keep you guys posted on my findings.

[190banshee]

Wow, thats a strange place to break the crank. Most that I've seen have broke at the clutch side where the shaft narrows.
I have a couple GPX and Jialing engines in my garage and the only difference I have noticed is in the trans. The GPX I have are 4up and the Jialings are 1D 3up but all the parts interchange. We had problems with 3rd gear in the 4 up trans but the Jialing has been flawless for over a year now and a dozen races, a few trips to Pismo and countless hours on the backyard track. I built 2 Jailings, 1 to race and 1 for a spare and so far the spare has just sat on the shelf.
Unfortunately the GPX/Jialing crank is not a replacement for the Typhoon with the 2 stage clutch.
Good luck with the rebuild.

[Ride1Rob]

It seems that the ordinary Jailing cranks aren't the issue. It's the semi-auto clutch cranks (Xtreme Typhoon) that are weak. Think I'm going to do away with the centrifugal clutch setup. Supposedly, the jailing bottom ends are tanks and are the best on the market and alot of pitbike racers are going to them because of this. But they aren't riding centrifugal clutch (Typhoon) bikes and the cranks that they're riding on (Jailing) are very durable.

[drxracing]

what kind of mods did the drr your son used have ????

[Ride1Rob]

Originally posted by drxracing
what kind of mods did the drr your son used have ????

Not sure but he said the motor was completely maxxed out. The bike was a 70 but the way he was talking I think maybe he had a 90 head on it or something. I'm not sure as he really wouldn't get into details with me :confused: .