rsheppick Posted April 17, 2006 Report Share Posted April 17, 2006 Thanks...Tim. I'm positive the slides are right...cutout towards the back. I'm very very good with these carbs. I do have an extra CDI sitting on the bench at my house. I think I may try that next... 503075[/snapback] Dajogejr, PM me your address, I will send you these 39MM if you want to test bigger carbs. They are of no use for me ATM. You didn't say if you tried a differnt CDI box... Have you measured the resistance between the pairs of leads off the stator? if you have a clymer please direct yourself to the top of page 223... Quote Link to comment Share on other sites More sharing options...
lowriderb Posted April 17, 2006 Report Share Posted April 17, 2006 the stock length studs should fit the noss machine head unless its possibly one of the very first designs out if i remember right.. im sure youve looked at it as well, but how about the reeds are they in check? not flexed too far out as well or broken or just cracked?.. i know a friend of mine had one of his reeds blown out (v force) and it would rev fine without a load on the motor but when moving it wouldnt pull up to get to the power band.. since you have a second "known" working cdi to spare you could try that out and see if it clears up the problem, while your at it as well you could pull out the ohm meter and make sure all the wires are still connected (no breaks ect..) how is your compression as well? im sure that youve possibly checked it buy now, but its always something you want to know.. also do you have clear fuel lines? if not, change them to something you can see through and see if your getting a flow from the gas tank.. i started out my last riding trip with that problem and couldnt understand why i wasnt getting it to run (just cutting out at about 1/2 throttle) tried making a pass and looked down at the fuel lines and bam mt.. i pulled the ball bearings out of the cap so there is no check valve in there anymore and that worked.. Quote Link to comment Share on other sites More sharing options...
strokersquid Posted April 17, 2006 Report Share Posted April 17, 2006 cut out should go towards the front, that is the air filter side not the reed side, right ? Quote Link to comment Share on other sites More sharing options...
wesw Posted April 17, 2006 Report Share Posted April 17, 2006 when you apply throttle and the bike acts up or bogs, at the moment pull the plug and see what it looks like. it will give you a better judgement. might be worth a shot. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted April 17, 2006 Author Report Share Posted April 17, 2006 rshe...thanks, but no thanks.... This is not a bigger carb problem. I know bigger carbs will give me 5 to 15 horse on top end. Smaller carbs should work better than large carbs on the small end...period. The cutouts go towards the air filter side. I'm workign with Jeff and DLNOss to get new studs and acorn nuts...and do it over again. I have a spare CDI given to me by a friend that sold his shee. I can't be 100% positive it is good, but...I'm going to try it anywho... Reeds are in great shape. No gap...no cracks, burns, etc. Stock cages, boyseen reeds. I just got the head last Wednesday...I'm sure it's a newer design...I'm sure Jeff sells enough of these to not sit around on the shelf!!! Quote Link to comment Share on other sites More sharing options...
race-a-holic Posted April 17, 2006 Report Share Posted April 17, 2006 I think you're right.Even with stock carbs it should rev.It might not have the power it would with larger carbs,but it still should be rideable.Not really sure what the problem is with everything you checked.So it will rev in nuetral and not in gear?Could it be a vacuum problem?Maybe an airleak somewhere?Just something to think about. If so,that could end up burning up your motor.Jeff should have some ideas with what to check. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted April 17, 2006 Author Report Share Posted April 17, 2006 Thanks...Race...that's exactly what I'm thinking... At this point...I thnk it's a spark issue. I closed the gap to .020 to see if it'd help...but then I noticed a bit of coolant on a head stud, pulled the head...and that's where it stands. It was 172 in one cylinder, 180 in the other.... I showed Jeff some pics of the cylinders...and the rings haven't even seated yet.... Quote Link to comment Share on other sites More sharing options...
odaen Posted April 17, 2006 Report Share Posted April 17, 2006 your stock carbs should work fine for now. would anything have caused the gab between the pickup coil and flywheel to change? also, just curious why you switched back to the stock needle? thought they were actually leaner than the toomey needle? like wes recommended, I'd fire it up and get it to the point that it bogs shut it off and look at the plugs. that motor should run very good, even with stock carbs and T5's. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted April 17, 2006 Author Report Share Posted April 17, 2006 Since it idled fine...started fine...but won't get past 1/8 throttle...I thought needles right off the bat. Others here go right to the main...but, I can't even get there... I took the whole ignition side apart to make sure the air gap was fine...it is. Also, to make sure there were no pinched wires, etc....there aren't. Like I said, it'll start and run fine. It will not take ANY gas once in gear going to take off.... Quote Link to comment Share on other sites More sharing options...
lowriderb Posted April 17, 2006 Report Share Posted April 17, 2006 also do you have clear fuel lines? if not, change them to something you can see through and see if your getting a flow from the gas tank.. i started out my last riding trip with that problem and couldnt understand why i wasnt getting it to run (just cutting out at about 1/2 throttle) tried making a pass and looked down at the fuel lines and bam mt.. i pulled the ball bearings out of the cap so there is no check valve in there anymore and that worked.. have you tried this as well? when mine did it it would rev fine with no load on the motor, but as soon as you tried running it moving anywhere it was a no go situation.. your issue may be more severe with the air lock on the tank than mine was.. Quote Link to comment Share on other sites More sharing options...
dajogejr Posted April 17, 2006 Author Report Share Posted April 17, 2006 (edited) I've got oversized fuel lines from the tank, nice clean T Fitting, and new lines to the carbs. I'm pretty sure it's getting gas...and plenty of it. I will...however, invest in clear lines just be be sure.... Again...if this was a top end issue, I could defintately see a shortage of gas...but, it can't be using that much at 1/8 throttle.... I do appreciate all the input...New Head studs, acorn nuts and washers on the way and will have tomorrow. Back to the drawing board... D"oh...just reread that... Just for giggles...I'll try loosening the gas cap till it almost falls off...and see what happens.... Edited April 17, 2006 by dajogejr Quote Link to comment Share on other sites More sharing options...
No Limit Powersports Posted April 17, 2006 Report Share Posted April 17, 2006 (edited) Sounds like your way to fat to me just because the bike needs more flow doesnt necessarly mean it needs bigger jets. This is where most people make mistakes, your main jet does not increase the flow into the motor it only increased the fuel in the air/fuel mixture. Ive built several cubs and found that they will run just fine with stock carbs in fact I had a 350 make 80 horse on stock carbs and a air box. The cubs flow so much more air that they actually pull on the main jet harder and cause a fat condition i dynoed a bike once that was a oem cylinder with stock carbs dialed in at a 340 main changed to a cub with the same compression and had to down jet to a 310. Stick a 320 in that sucker and see what it does. Not saying that this is your problem may have other issues but a 380 sounds like way to much jet... Edited April 17, 2006 by bansheestang Quote Link to comment Share on other sites More sharing options...
dajogejr Posted April 17, 2006 Author Report Share Posted April 17, 2006 (edited) You know...another friend of mine said the same thing. The cub actually makes the stock carbs much, much more efficient...and it might not need as much main... But, 380 to 350 yielded no changes...and, I'm still not able to get past 1/8 throttle. Once I get it back together, I'm going to loosen the gas cap to make sure i'm not locking it in vacuum...and changing the CDI with one I have laying around. If that still doesn't cure it...then, I'm going to lean out the needle first...then main. I can tell you going from a 27.5 pilot to 25 (stock) it did start and idle better... Edited April 17, 2006 by dajogejr Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted April 17, 2006 Report Share Posted April 17, 2006 Sounds like your way to fat to me just because the bike needs more flow doesnt necessarly mean it needs bigger jets. This is where most people make mistakes, your main jet does not increase the flow into the motor it only increased the fuel in the air/fuel mixture. Ive built several cubs and found that they will run just fine with stock carbs in fact I had a 350 make 80 horse on stock carbs and a air box. The cubs flow so much more air that they actually pull on the main jet harder and cause a fat condition i dynoed a bike once that was a oem cylinder with stock carbs dialed in at a 340 main changed to a cub with the same compression and had to down jet to a 310. Stick a 320 in that sucker and see what it does. Not saying that this is your problem may have other issues but a 380 sounds like way to much jet... 503507[/snapback] this is very true. at the HQ ride i had like 170s in my "bigger" cub motor..it ran like shit so i was thinknig bigger jets but the plugswere black. ended up dropping way back down to a 160 and it ran alot better besides the sweet cutting out on the top due to my pipes(i think)...maybe try some 300 mains in there and see what happens...have you checked your plugs yet??? Quote Link to comment Share on other sites More sharing options...
dajogejr Posted April 17, 2006 Author Report Share Posted April 17, 2006 Geez...Loco...bout time you chimed in.... They are wet...a little gray for my taste. But, then again it's only run for less than 15 minutes or so total. I'm going to wait going any smaller on the mains until I get my head back on...and swapping CDIs. Then...I'll start with a leaner needle clip. It's going to be some simple tuning...throwing bigger carbs at it for the sake of "it'll run better" is not the answer here.... Quote Link to comment Share on other sites More sharing options...
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