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Should have bought an Austrian electric. KTM SX-E 2 or the Husky or Gasgas equivalent
Just ordered boyesen reeds, piston/rings, high compression head, bearing kit for output shaft, and stiffer clutch springs. I’m wondering if I should have gotten a cylinder too. I did pull the exhaust and silencer apart and there was very little carbon on it. I think I’m also going to just pull the gear off the oil pump and run premix and see if that helps too.
You need to get it running right first
You are going be chasing your tail forever like soggy says you need to get it running correctly first. Damn mini dads. 😎
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I’m out of ideas man. At this point I’m thinking maybe we’re just asking too much of it with my kid weighing almost 50lbs. It does just fine in the yard but will struggle on a track with some hills, and even worse when it’s been disked up.
Dont do stiffer clutch springs or head. Do all OEM.
Get the oil pump tuned, I recommend MCP, but lots of builders around and cheap to tune. Oil Pump and Carb Tuning, right gas, with fresh top end and clutch springs and itll run good. This one is all stock minus race gas and tuned pump for 50:1 and it runs pretty good. But his full prep PW still runs faster because of better bearings, balanced crank,.etc.
Get it running good stock then work your way up on mods or I think youll be chasing yourself like others said.![]()
It runs well and rips around the yard just fine, it just struggles on a track. I’ve been messing with it for some time now and I think I’m looking for something that just isn’t there. Spark plug is new, no issues found with the choke, carb is clean and I put in the 67.5 main everyone recommends, good fuel, using the right injection oil, twin air filter with a very light coat of oil, exhaust/silencer are clean, drained crankcase oil and measured it to make sure it isn’t burning it, made sure brakes aren’t dragging. I’m sure there’s other things I’ve done I’m forgetting. If you’ve got some other things I can check please let me know, I’ll be honest I don’t know much about these little things lol.
I do think it will benefit most from having the injection pump tuned. But for now I think I will just remove the gear, plug the line, and use premix.
Curious why you don’t recommend a high compression head? I bought the “50cc rebuild kit” from peewee cycle which includes a piston, cylinder, and a high compression head. If it’s really that bad I’ll just reuse the OEM head. I was a little unsure about the stiffer clutch springs, I don’t want to make it harder to ride, I just want to do everything I can to help this thing get around a track.
I had one with a lot of carbon build up on exhaust port in cylinder. It was restricted bad by it.
Send to Cycleworx, itll rip
As someone with years of experience with these bikes, this guy gave the best advice so I will just add a couple comments. Make sure you are buying everything OEM except for bearings and an adjustable needle for the carb, especially if you are running any AMA events.
For our practice PW (non cycleworx):
Stock air filter (light coat of WD40)
67.5 main running U4.4
BPR6HS plug
If you choose to run a leaded fuel I would suggest running Redline oil as it reduces the amount of leading on the plug.
Drill out that air screw if you haven't yet. Best way to tune these is to get it warm on a stand, run the idel screw in the whole way then run the air screw in the whole way, turn the air screw out slowly (our stock one is 1.5-2 turns out) until that bike sounds like a Stihl chainsaw!
B&M trick shift in the case (250cc)
Striping all of the factory grease out of the rear end and applying a thin coat of grease will help reduce drag a lot also. (this does become a maintenance item if you choose to do it).
Cycleworx or Pax for the parts is your best bet. We choose Cycleworx for everything since they built our motor and Joe is very helpful when you have any questions. Hope this helps!
I had the exact same problems. My son would get stuck going uphill no power. I tried everything and then I found the real problem. The packing in the end of the pipe is soaked with oil causing heavy restriction, push it out and discard, the bike now rips!
With insurance issues and such alot of tracks are becoming AMA events and the AMA rules are pretty specific on a PW (you cant even unplug the kill start/run switch). If you havent drilled out the air screw plug yet id start there, there is a lot of gains to be had there by getting that thing dialed in..The motors on these are pretty simple, so something is keeping it from pulling around the track, it has to be top end, clutch, air/fuel mixture, or drive shaft related.
I'd get it as close as I can to stock and see if you can get it performing "normal" then start modding. PAX or Aftermarket Minis make easy to install oil pump plugs. Or there are some guys who will tune your oil pump free if you send to them.
WD40 on the air filter, clean every ride, and clean oil pump housing. And make sure main jet 100% clean. Last race we did ours had the smallest spec of sand and ran fine on gate, but got to first jump and wouldnt pull him up it.
Also make sure your bowl and overlow hoses clean, they can gunk up.
Also make sure you have good back tire not stock. Dunlop Fronts and turn around backwards.
Idk how to attach videos, but i can send you a video of his race prep PW and how it sounds.
Easy way to diagnose if this is your issue. Take the exhaust off and run it around the yard. You will be able to tell pretty quickly if the plugged exhaust is your issue. I am betting it is.
Unpopular take- kids should not be allowed to race PW’s. Solve all the problems in one shot. Let kids learn how to ride first. The bikes suck, and the chassis is over ridden at anything over 10mph.
Yeah that will be unpopular for a reason.
My kid loves his PW, helps him build confidence. He also just got on a KTM Sr. I do agree that that chassis is sometimes sketchy when they get up to speed, but it teaches them to line search vs going right down the goat trail. But also agree that parents need to realize the sport so much bigger than PW days, and if you're kid isn't fast on a PW or any 50 that's okay, they might be a totally different rider on a 65 when the clutch and shifting come into play. Same thing for parents who think their kids are studs on 50s; 65s might humble them. In other words, enjoy the 50 days with your kid, let them fall in love with the sport...but it doesn't mean dad might not spend a little extra to get the 50 running hard
Definitely am enjoying these days! Just want to give him a bike he can make it around the track on haha. Check out this cylinder I just got from peewee cycles lol I don’t think I’ll be putting this on the bike.
Pit Row
Bruh… They sent that to you ? Hope you’re sending it right back, that’s not going to help anything here. lol
Did they let a 4 year old to do the porting on that thing? 😳
Our daughter at Jack Murphy stadium, I'm working on one for her 2 daughters right now. Call me crazy but I'm going to leave it stock. Our kids rode that bike all over Ocotillo Wells and the high desert for years. Only had to go on a rescue mission one time with that bike. And it was just because it got so muddy the front wheel wouldn't roll lol
The KTM Pro Jr. on the other hand took lots of rides on the tow truck. 😒I nick named it the ATM
I emailed them about it Friday and send pictures. They apologized they missed that and said to just throw it away and they are refunding me for the kit. Very quick response from them and they are making it right, very happy with that. I wasn’t even mad honestly, I’ve never seen one so bad… I got a good laugh out of it haha.
"Just throw it away"
Hahahaha! Yeah, that one ended up in the wrong bin at Pee-Wee.
Glad they're making it right.
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