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View Full Version : TMaxx 3.3 lost it's wheelies.


Bradley V. Stone
Sep 17, 2006, 11:11 PM
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!

kenji
Sep 17, 2006, 11:11 PM
In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:

> Thanks for any suggestions!

slipper clutch?

Bradley V. Stone
Sep 17, 2006, 11:11 PM
kenji wrote:
> In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:
>
>
>>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.

GTD
Sep 18, 2006, 01:11 AM
On Sun, 17 Sep 2006 22:04:26 -0500, "Bradley V. Stone"
<bvstone@nospam.yahoo.com> wrote:

>kenji wrote:
>> In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:
>>
>>
>>>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.

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. . .

DanTXD
Sep 18, 2006, 07:11 AM
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
news:4ebcf$450e0c44$41a099a1$1055@myclearwave.net. ..
> kenji wrote:
>> In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:
>>
>>
>>>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.

The hanging at flat low revs does sound like a lean low end to me...?

What clutch is it you're running, stock?

--
Dan

Bradley V. Stone
Sep 18, 2006, 09:11 AM
GTD wrote:
> On Sun, 17 Sep 2006 22:04:26 -0500, "Bradley V. Stone"
> <bvstone@nospam.yahoo.com> wrote:
>
>
>>kenji wrote:
>>
>>>In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
>>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:
>>>
>>>
>>>
>>>>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.
>
>
> 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. . .
>
>

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.

Bradley V. Stone
Sep 18, 2006, 09:11 AM
DanTXD wrote:

> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
> news:4ebcf$450e0c44$41a099a1$1055@myclearwave.net. ..
>
>>kenji wrote:
>>
>>>In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
>>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:
>>>
>>>
>>>
>>>>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.
>
>
> The hanging at flat low revs does sound like a lean low end to me...?
>
> 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. :)

DanTXD
Sep 18, 2006, 11:11 AM
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
news:3023$450e9518$41a099a1$12802@myclearwave.net. ..
> DanTXD wrote:
>
>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
>> news:4ebcf$450e0c44$41a099a1$1055@myclearwave.net. ..
>>
>>>kenji wrote:
>>>
>>>>In article <1d866$450e05c9$41a099a1$31635@myclearwave.net>,
>>>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote:
>>>>
>>>>
>>>>
>>>>>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.
>>
>>
>> The hanging at flat low revs does sound like a lean low end to me...?
>>
>> 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. :)

Any chance the clutch has been overheating and is glazed?

--
Dan - on his PC

Bradley V. Stone
Sep 18, 2006, 11:11 AM
DanTXD wrote:
> 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.

DanTXD
Sep 18, 2006, 01:11 PM
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
news:da4fb$450e9c5a$41a099a1$15509@myclearwave.net ...
> DanTXD wrote:
> > 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.
>

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...

--
Dan - on his PC

Bradley V. Stone
Sep 18, 2006, 03:11 PM
DanTXD wrote:
> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
> news:da4fb$450e9c5a$41a099a1$15509@myclearwave.net ...
>
>>DanTXD wrote:
>> > 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.
>>
>
>
> 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...
>

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.

DanTXD
Sep 18, 2006, 03:11 PM
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
news:94ec5$450ed302$41a099a1$3434@myclearwave.net. ..
> DanTXD wrote:
>> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
>> news:da4fb$450e9c5a$41a099a1$15509@myclearwave.net ...
>>
>>>DanTXD wrote:
>>> > 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.
>>>
>>
>>
>> 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...
>>
>
> 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.

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.

--
Dan

\Doc\
Sep 18, 2006, 07:11 PM
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
news:1d866$450e05c9$41a099a1$31635@myclearwave.net ...
> 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!

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

Bradley V. Stone
Sep 18, 2006, 09:11 PM
"Doc" wrote:
> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
> news:1d866$450e05c9$41a099a1$31635@myclearwave.net ...
>
>>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!
>
>
> 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?

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
>
>

GTD
Sep 18, 2006, 11:11 PM
>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
>
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

GTD
Sep 19, 2006, 11:11 PM
On Mon, 18 Sep 2006 17:06:43 +0100, "DanTXD" <me@privacy.net> wrote:

>IMHO the stock clutch is a
>bit limp anyway...
It's limp even for the 2.5

Bradley V. Stone
Sep 21, 2006, 05:11 PM
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

DanTXD
Sep 21, 2006, 05:11 PM
"Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
news:b9e09$4512e5d4$41a099a1$18177@myclearwave.net ...
> 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 :)


--
Dan - on his PC

Bradley V. Stone
Sep 21, 2006, 07:11 PM
DanTXD wrote:
> "Bradley V. Stone" <bvstone@nospam.yahoo.com> wrote in message
> news:b9e09$4512e5d4$41a099a1$18177@myclearwave.net ...
>
>>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! :)

GTD
Sep 21, 2006, 09:11 PM
>
>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. . ..

Bradley V. Stone
Sep 21, 2006, 11:11 PM
GTD wrote:
>>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..