 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
| HomeDiscussion Groups General ModelsRailroadsRocketsRadio Controlled Air ModelsHelicoptersLand ModelsWater ModelsModelGeeks.com Contact UsLink To UsSearch & Site Map |
Model Forum / Radio Controlled / Land Models / September 2006TMaxx 3.3 lost it's wheelies.
Hi, all. Once I got the 3.3 broken in (heat cycle) the thing ran like a scalded bear, rode wheelies until I decided to let it down, etc. Temps after 2-3 high speed runs were in the 250s or so (ambient temps around 75). Revs great, is super fast, decent smoke. But now wheelies went away. I think it's because the LSN is too rich, but if I go leaner on it after a WOT run the idle hangs pretty high for a few seconds while slowing down (and you can hear the clutch chattering sometimes). Then I thought maybe the clutch was going out as I noticed it jerking when using the EZ start. Took it apart, clutch looked a little worn (maybe 3 gallons through it now, with just over 1 on the engine) but nothign serious. Checked the bearings on the clutch and one was sticking a little. Cleaned it up. Jerking while starting went away. Still no wheelies. I do a 15 second idle then JAM and it's like it stays at a lower RPM for 1-2 seconds while moving then takes off smoothly and at a pretty even (but fast) rate (no burbling, lean hesitation, etc, just a flat sound). Weak clutch spring causing it to engage too early before it hits the lowend power to take off? Or maybe I need to go further with the HSN tuning and revisit LSN? It's at the point now where it does scream. Richen it 1/4 turn and you can tell a HUGE difference with a big power drop and lots more smoke. Also using pinch test on LSN. RPMs rise a little and die at 2-3 seconds. Any leaner and no rise in RPMs during pinch test. Any richer and RPMs go up too high before dying (but still 3-4 seconds) and bottom end seems to get worse. Have about 3 gallons on the clutch and 1-1.5 on the motor (which still has great pinch). Yes, I smoked the rod on my first motor.. :) I blame it on the Traxxas break in.. lol Thanks for any suggestions! > Thanks for any suggestions! slipper clutch? >>Thanks for any suggestions! > > slipper clutch? Nope, checked that.. it's all good. When I noticed it wouldn't wheelie as easy any more I retuned from factory. Ended up in the same place and still no wheelies. It just seems the RPMs hang at a lower RPM while taking off.. any leaner, well, WOT runs end in high hangling idle for a couple seconds, erraticle idle, etc. Maybe idle is too high? It wouldn't even start at flush for the LSN until I richened it up. >>>Thanks for any suggestions! >> [quoted text clipped - 9 lines] >erraticle idle, etc. Maybe idle is too high? It wouldn't even start at > flush for the LSN until I richened it up. Just for the sake of being thorough (sp?), Try fattening up the LSN a little, , ,every motor I have seems to like being a little fatter on the bottom end than most people reccomend. . .Does the 3.3 use the same weenie clutch that the 2.5 revo does? I wouldn't expect that to last too long. . . >>>>Thanks for any suggestions! >>> [quoted text clipped - 15 lines] > same weenie clutch that the 2.5 revo does? I wouldn't expect that to > last too long. . . I tried that too. It seemed to make it even worse, which is why I was assuming it was lean. But maybe I didn't go far enough. I can tell it's too fat on the bottom because when I putt putt around slowly (1/4 throttle or so) and then stop, idles kick way down and sometimes it dies. So if I 'm driving slow I need to clean it out really quick before coming to a stop.. huge puff of smoke comes out after that. :) Clutch is probably the same as the 2.5 revo. Not sure. >>>Thanks for any suggestions! >> [quoted text clipped - 9 lines] > idle, etc. Maybe idle is too high? It wouldn't even start at flush for > the LSN until I richened it up. The hanging at flat low revs does sound like a lean low end to me...? What clutch is it you're running, stock?  SignatureDan >>>>Thanks for any suggestions! >>> [quoted text clipped - 13 lines] > > What clutch is it you're running, stock? Yep, clutch is stock. I've tried richening.. seems to get worse and causes stalling after low speed runs (flameouts). I think these motors need more than 2 adjustments. :) >>>>>Thanks for any suggestions! >>>> [quoted text clipped - 18 lines] > > I think these motors need more than 2 adjustments. :) Any chance the clutch has been overheating and is glazed? SignatureDan - on his PC > Any chance the clutch has been overheating and is glazed? I gave it a light sanding when I checked it out. Didn't look glazed, but a little scuffing never hurts. One thing I did notice is in a couple spots the material was worn down to almost the level of the spring. > > Any chance the clutch has been overheating and is glazed? > [quoted text clipped - 3 lines] > One thing I did notice is in a couple spots the material was worn down to > almost the level of the spring. Those spots are pretty much the only places those clutches engage - same as the one in my Revo. That means it's pretty worn, maybe take this opportunity to upgrade to the 3 shoe setup - as IMHO the stock clutch is a bit limp anyway... SignatureDan - on his PC >> > Any chance the clutch has been overheating and is glazed? >> [quoted text clipped - 8 lines] > opportunity to upgrade to the 3 shoe setup - as IMHO the stock clutch is a > bit limp anyway... Where do I get the 3 shoe setup? And what if I flipped the shoes for now so they are the opposite facing way? I hear that makes them engage later and I may get a few more tanks out of them. Thanks. >>> > Any chance the clutch has been overheating and is glazed? >>> [quoted text clipped - 14 lines] > > Thanks. Hmm dunno, don't have much experience of these types of clutch - the 3 shoe setup is a Traxxas optional hopup though IIRC, so it can't be that hard to find, Tower probably sells it. SignatureDan > Hi, all. > [quoted text clipped - 37 lines] > > Thanks for any suggestions! Have you checked for exhaust header and coupler leaks? Checked/Replaced the fuel hoses? Checked the fuel filter? Changed the glow plug to something a bit hotter? Verified that the slide is opening all the way when you pull the trigger? Perhaps bought a bad batch of fuel? Checked the driveline for binding? Checked the brakes to make sure they ain't dragging? Checked the air filter to see if it's excessively dirty? It really <sounds> like a slight lean bog, but if richening the LSN and/or HSN didn't help matters, it ain't that. It sounds like you know what you're doing and that you've tried all of the common sources of this problem. I doubt it's the clutch as others have suggested as a worn clutch causes RPM to increase d/t slippage rather than decrease RPM, but hey, you never know! HTH, Doc >>Hi, all. >> [quoted text clipped - 47 lines] > Checked the brakes to make sure they ain't dragging? > Checked the air filter to see if it's excessively dirty? Yep, checked all that. The only other change made was adding RDLogics driveline shafts. Now, this COULD be the problem but IIRC it started happening before this. Seems to roll just fine. Brake are adjusted (were too loose before and disc fell off causing a front flip), no leaks, etc. I may try just richening up the LSN a little more to see how much worse it may get. But, pinch test tells me that it's getting rich even with 1-2 hours richer. So does drivability. It's already at least a turn out past flush... I know all machines are different, but this is my 2nd 3.3 and never would it even run at flush (too lean). Richer than I have now, drive around slowly and it bogs pretty bad and if it dies, starting it is like restarting after killing it by plugging the exhaust.. a little hard. Vs. starting it after a pinch test where it starts right back up in a millisecond with EZ Start. > It really <sounds> like a slight lean bog, but if richening the LSN and/or > HSN didn't help matters, it ain't that. The best way to describe the sound is "riding the clutch" on a dirt bike. The sound itself doesn't tell me rich or lean (no crackling/hesitation or bogging/4 stroking). > It sounds like you know what you're doing and that you've tried all of the > common sources of this problem. I doubt it's the clutch as others have > suggested as a worn clutch causes RPM to increase d/t slippage rather than > decrease RPM, but hey, you never know! That's what I've found with these little buggers. You never know. :) Tuned bikes and quads for years and this proved similar, but something like this baffles me a bit and process of elimination starts up. :) > HTH, > > Doc >> It sounds like you know what you're doing and that you've tried all of >> the common sources of this problem. I doubt it's the clutch as others [quoted text clipped - 4 lines] > Tuned bikes and quads for years and this proved similar, but something > like this baffles me a bit and process of elimination starts up. :) Oh man you wouldn't *beleive* the amount of times we've just had issues appear for no visible reason, only to completely clear up after the next run! With the 3.3 I'd be tempted to go for the clutch upgrade anyway you know, I actually thought Traxxas did one as a hopup, but it appears I might have been talking out of my a.s as I can't find it anywhere on the website :) Although, I did notice you can now get red adonised alu wheels with real rubber tyres for your wheelie bar haha :-D The stock clutches are cheap enough to change one out just to see if it makes a difference I reckon, also, tighten the slipper clutch up a bit more (I've never been a fan of this backing off a quarter turn malarky). Oh BTW, have you changed your suspension setup at all? SignatureDan - on his PC > Oh man you wouldn't *beleive* the amount of times we've just had issues > appear for no visible reason, only to completely clear up after the next [quoted text clipped - 9 lines] > > Oh BTW, have you changed your suspension setup at all? Slipper on the 3.3 is different than the 2.5. Basically you tighten it until you can just barely move it with your finger turning the spur while holding the other side of the shaft. I've tightened it more to make sure, nothing different. :) I have added stiffer springs and went up to 50w oil in the shocks all around. I didn't see any leaks but I know that if the rear end did get softer, that could be an issue. The RDL center CVDs are what bug me. Good looking, strong as heck, but metal on metal? The stockers may not be as strong but at least they had real joints. :) Not a dogbone in a slot.. lol. Now, if there were covers and you pack em with grease, that may help. The diff ends did have dust covers, but they split after the first run..lol.. If you are supposed to grease them, who's to know.. RDL supplied zero install instructions. The other day when I was running it I could get it to wheelie by blipping a few times, then it came up a little. And right when it was going dry and leaning out, I got a killer wheelie.. lol... which also tells me rich. So maybe I should ask. When tuning the HSN I stopped after it got what I considered good sound and performance. I tried to keep going and performance didn't seem to get much better, but it also never started to cough from being to lean.. But, from where I have it 1/4 turn richer and it goes from a screamer to a slow smoking machine.... 1/4 to 1/2 turn leaner and it doesn't seem to get much better performance, just less smoke. :) Maybe I haven't gone far enough on the HSN yet? Fresh plug and 3 tanks later plug base shows a very light tan.. which is good. But maybe it's still too rich and should colorize quicker? 1st tank was still shiny. Lots of high speed runs. :) >> Oh man you wouldn't *beleive* the amount of times we've just had issues >> appear for no visible reason, only to completely clear up after the next [quoted text clipped - 44 lines] > good. But maybe it's still too rich and should colorize quicker? 1st tank > was still shiny. Lots of high speed runs. :) If it's not getting any quicker, personally I'd back it off till the richest I could have it, without losing any performance. Doc will tell you the same if I recall correctly, and he's jsut got 16 gallons out of an S25 - you just can't argue with that :-). The reasons for your lack of wheelies sound like, GTDs suggestion of the spring lost it's tension, and the softer rear end will DEFINATELY hurt it's wheelying - like, massively. Suspension can have more effect than gearing IME. If you want wheelies back, stiffen the rear end up with a preload clip on each (or are they threaded?). SignatureDan - on his PC >>>Oh man you wouldn't *beleive* the amount of times we've just had issues >>>appear for no visible reason, only to completely clear up after the next [quoted text clipped - 55 lines] > IME. If you want wheelies back, stiffen the rear end up with a preload clip > on each (or are they threaded?). Ya, I'll try a bigger clip first to see if that helps. Maybe the springs are wearing on the shocks... oh well.. Thanks! Check your muffler for a leak. I have seen the mufflers split at the seam, and if your engine is too lean you can burn out the baffle inside the muffler causing the engine to loose power. >>>>Oh man you wouldn't *beleive* the amount of times we've just had issues >>>>appear for no visible reason, only to completely clear up after the next [quoted text clipped - 58 lines] > Ya, I'll try a bigger clip first to see if that helps. Maybe the springs > are wearing on the shocks... oh well.. Thanks! SignaturePosted via a free Usenet account from http://www.teranews.com >It sounds like you know what you're doing and that you've tried all of the >common sources of this problem. I doubt it's the clutch as others have [quoted text clipped - 4 lines] > >Doc The Revo clutch has only a pair of shoes, and a tension spring the wraps around the pair holding them in. If that spring gets too hot, it looses it's tension and the clutch engages way early. Funny thing is, at least on my kid's revo, it didn't creep at all, the clutch just came in all the way right after idle and it completely killed the bottom end. . . it's not just a matter of the shoes wearing and slipping Got a new clutch and spring set at the LHS. Old spring was definatly worn. I could barley get the new one over the new shoes it was so tight. Once it quits raining.. we'll see if it was the issue.. lol > Got a new clutch and spring set at the LHS. Old spring was definatly > worn. I could barley get the new one over the new shoes it was so tight. > > Once it quits raining.. we'll see if it was the issue.. lol Report back when sorted :) SignatureDan - on his PC >>Got a new clutch and spring set at the LHS. Old spring was definatly >>worn. I could barley get the new one over the new shoes it was so tight. >> >>Once it quits raining.. we'll see if it was the issue.. lol > > Report back when sorted :) Checking the weather it doesn't look like it's gonna let up for a couple days.. Bummer! I wanna see the wheelies again! :) >Checking the weather it doesn't look like it's gonna let up for a couple >days.. Bummer! I wanna see the wheelies again! :) Just run it in the living room, , ,if you do it real quick, when nobody else is home they won't even notice. . .. C'mon, you know you want to. . .. >>Checking the weather it doesn't look like it's gonna let up for a couple >>days.. Bummer! I wanna see the wheelies again! :) > > Just run it in the living room, , ,if you do it real quick, when > nobody else is home they won't even notice. . .. C'mon, you know you > want to. . .. Don't think I haven't thought about it.. lol.. |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.