R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Nitro On-Road

Reply
 
Thread Tools Search this Thread
Old 11-20-2003, 07:11 AM   #1126
Tech Regular
 
Join Date: Sep 2003
Location: Hong Kong
Posts: 277
Send a message via ICQ to lawndoggie Send a message via Yahoo to lawndoggie
Default

Quote:
Originally posted by Diesel Racer
Thanks for the offer lawndoggie, you are a true gentleman but I really got to have one before then, perhaps you could suggest a decent LHS that will ship to the UK.
I totally understand! Who would want to wait 5 months!!
Check out Harmony and World Model. They'll both give you the same price. World Model is the distributor here in HK, where I bought the 705:
http://www.worldmodel.com.hk

but they might just ask you to get it from you LHS!
lawndoggie is offline   Reply With Quote
Old 11-20-2003, 08:51 AM   #1127
Tech Regular
 
fmolzer's Avatar
 
Join Date: Jul 2002
Posts: 467
Default

Quote:
Originally posted by markp27
Water expands dramatically and with a very large force when frozen and you'd probably end up with a completely split pipe - I wouldn't do it.
If it were possible to seal both ends somehow and stick the pipe in boiling water to allow the air pressure to push the dent out, that'd be ok, but I doubt you can seal the pipe effectively.

Cheers, Mark.
I usually allow for this by just plugging the stinger and the pressure fitting. (run fuel tubing from one to the other) Then, fill the pipe with water, but leave the hole uncovered (connection at manifold) Stand the pipe up in the freezer so no water spills out. The ice will start to form on the uncovered hole first, creating an ice cover, then inside the pipe so the dings gets pushed out. The ice cover will start to push up if the ice inside the pipe can't expand the pipe itself anymore. This happens way before the pipe would become damaged from the expanding ice. Works every time
fmolzer is offline   Reply With Quote
Old 11-20-2003, 09:07 AM   #1128
Tech Regular
 
Join Date: Sep 2003
Location: Hong Kong
Posts: 277
Send a message via ICQ to lawndoggie Send a message via Yahoo to lawndoggie
Default

kool kool! got to try it tonite!
Whats the "chariteristic" of having front tires harder than the rear? for example 40 front and 37 rear? comparing to say 40/40?

Thanks
lawndoggie is offline   Reply With Quote
Old 11-20-2003, 09:33 AM   #1129
Tech Apprentice
 
Join Date: Nov 2003
Posts: 50
Default

Quote:
Originally posted by InitialD
Michael, your suggestion seems to suggest to make the car have more on power steering with more caster and less rear toe in...

Like what RacerDude mentioned, shouldn't the rear toe in be more for technical tracks to prevent on power oversteer? Besides for a small track, scrubbing speed in the straight line is not so important and using more rear toe in, your rear is more stable.

I think in my opinion, to get more turn in the sharp corners and apexes, less caster is required...

I would agree on the open / looser diff though.
Well, the problem with rear toe is that it takes away steering! No matter if you are on or off throttle! It also takes away top speed!
So the goal should be as little as possible.
With the 705 my problem was usually turn-in oversteer, never on-throttle. Of course this also depends on the differential settings.
So again: a loose diff will make your car turn in faster but will create understeer out of the turn.
More rear toe will creat more understeer (or more rear traction) off and on-throttle.
Caster is more difficult. With more caster the inside rear wheel will lift more, when you turn the wheels. Because of that effect you actually gain steering (or loose rear traction). On the other hand you have less front rubber touching the surface because the inside wheel will run more on it's edge.
If you gain steering or not with more caster may depend on your diff settings. If you run a tight diff or solid rear axle, you will gain steering on and off throttle, because the lifted inside rear wheel will help the car to turn. With an open diff you don't need to lift the inside wheel, in that case the car may turn better with more front rubber on the street, which means less caster.
Something to think about!
MichaelS is offline   Reply With Quote
Old 11-20-2003, 09:57 AM   #1130
Tech Prophet
 
InitialD's Avatar
 
Join Date: Feb 2002
Location: MORDOR
Posts: 19,679
Default

Quote:
Originally posted by MichaelS
Well, the problem with rear toe is that it takes away steering! No matter if you are on or off throttle! It also takes away top speed!
So the goal should be as little as possible.
Agreed.

Quote:
Originally posted by MichaelS
So again: a loose diff will make your car turn in faster but will create understeer out of the turn.
Agreed.

Quote:
Originally posted by MichaelS
More rear toe will creat more understeer (or more rear traction) off and on-throttle.
Ummm, on throttle understeer yes but off throttle understeer with more rear toe in is new to me..

So when do you use more rear toe in then? Larger tracks? Wouldn't that take away top speed?

Quote:
Originally posted by MichaelS
Caster is more difficult. With more caster the inside rear wheel will lift more, when you turn the wheels. Because of that effect you actually gain steering (or loose rear traction). On the other hand you have less front rubber touching the surface because the inside wheel will run more on it's edge.
Agreed.

Quote:
Originally posted by MichaelS
If you gain steering or not with more caster may depend on your diff settings. If you run a tight diff or solid rear axle, you will gain steering on and off throttle, because the lifted inside rear wheel will help the car to turn. With an open diff you don't need to lift the inside wheel, in that case the car may turn better with more front rubber on the street, which means less caster.
Something to think about!
Woow, yes... Definitely something to think about ! Read it a few times to digest.

The last info is totally new to me. So what you're saying is the drag on the harder rear diff (or solid axle) when off power will assist in steering the car, which will be greatly amplified when you have more caster? This is with one way front right? Cool. What about turning radius?

So what you're also saying is the caster's characteristics only apply conventionally when the rear diff is loose?

When you say more steering (off power), how would you describe it? Faster and more responsive turn in with smaller turning radius? I always thought this was a function of the caster (i.e. less caster, faster turn in) regardless of the rear diff setting.
InitialD is offline   Reply With Quote
Old 11-20-2003, 11:12 AM   #1131
Tech Fanatic
 
Julius's Avatar
 
Join Date: Oct 2003
Location: Amsterdam Netherlands
Posts: 979
Default

Quote:
Originally posted by InitialD
Ummm, on throttle understeer yes but off throttle understeer with more rear toe in is new to me..

So when do you use more rear toe in then? Larger tracks? Wouldn't that take away top speed?
When you run rear toe in two things happen.

First realise that when cornering the outside wheel does most of the work. That means if you run toe-in on the rear the outside wheel will be pointing to the inside of the corner.
Because of this the car rotates less aound the top axis but also moves sideways. Therefore the front will need to turn more to compensate this effect = less steering.

On throttle toe-in has a stabilising effect. Now the wheel not only points to the inside of the corner, but the acceleration force of the wheel will also be directed that way. This counteracts in part an oversteer situation.
Under braking unfortunately things are reversed. The braking force in this case actually pulls the rear out of line. So more toe-in will not help a car that is unstable during braking.

It has not a lot to do with big or small tracks. I set toe to be a compromise. I will try to run as little as possible and use it to balance the car under acceleration.
Julius is offline   Reply With Quote
Old 11-20-2003, 11:13 AM   #1132
Tech Champion
 
Join Date: Sep 2002
Location: Chicago Illinois USA
Posts: 9,107
Trader Rating: 16 (100%+)
Send a message via ICQ to Solara Send a message via AIM to Solara
Default

Hey InitialD.......any idea where is "ammdrew"..? Back then at HPI forum and here, he was very active and I found him very helpfull on Impulse....did he jumped the wegon to Mugen or NTC3 or Retired...?
Solara is offline   Reply With Quote
Old 11-20-2003, 11:20 AM   #1133
Tech Elite
 
markp27's Avatar
 
Join Date: Jan 2003
Location: Nuremberg, Germany
Posts: 4,069
Send a message via ICQ to markp27
Default

Hi Julius,

Is there some basic rules about downstop settings for small tracks?

Cheers, Mark.
markp27 is offline   Reply With Quote
Old 11-20-2003, 11:22 AM   #1134
Tech Fanatic
 
Julius's Avatar
 
Join Date: Oct 2003
Location: Amsterdam Netherlands
Posts: 979
Default

Quote:
Originally posted by InitialD

So what you're also saying is the caster's characteristics only apply conventionally when the rear diff is loose?
Here also two things interact. The diff and caster work together.

Caster makes the car roll sideways. This is because when you turn the wheels part of the rotation is in an up and down movement of the wheel (more with a lot of caster, less with small caster angles).

If you run a solid axle and have no caster and turn the front wheels in a corner, the car will have difficulty to turn in. This is like a flintstone car. If you were to use a lot of caster, the chassis roll will lift the inside wheel off the ground and the car will turn in much easier.

If you run a loose diff the car will turn in easy because the diff allows the rear wheels to turn at different speeds. If you would run a loose diff and a lot of caster, the turn in wouldn't change so much but you could lose a lot of drive out of the corner. The caster lifts the inside wheel and the loose diff will put all the power to the wheel that is off the ground.

So caster and diff will need to work together.
Julius is offline   Reply With Quote
Old 11-20-2003, 11:30 AM   #1135
Tech Fanatic
 
Julius's Avatar
 
Join Date: Oct 2003
Location: Amsterdam Netherlands
Posts: 979
Default

Quote:
Originally posted by markp27
Hi Julius,

Is there some basic rules about downstop settings for small tracks?

Cheers, Mark.
First of all downstop means the limit on the downtravel of the suspension (droop limit). I saw somebody using up and downstop the other way around (that is maybe more logical but not the "widely used" explanation).

Rear downstop has most effect on braking. In general more downstop (less rear downward movement of the suspension) gives more stability under braking. But limiting suspension movement is generally less good in bumpy conditions.

Front downstop effects the on power steering. If you run more front movement you get a little more on power steering (the front wheels stay on the ground longer). But if you go too far the car's response slows down and could get vague out of the corners.

In a small track with lots of corners you'd expect more downstop (less suspension travel) gives best results because the car responds quicker. Try to always keep the car "in the springs" so if the car is stationary on the table you can lift the chassis a little before the wheels come off the ground.
Julius is offline   Reply With Quote
Old 11-20-2003, 11:38 AM   #1136
Tech Elite
 
markp27's Avatar
 
Join Date: Jan 2003
Location: Nuremberg, Germany
Posts: 4,069
Send a message via ICQ to markp27
Default

Quote:
Originally posted by Julius
Rear downstop has most effect on braking. In general more downstop (less rear downward movement of the suspension) gives more stability under braking. But limiting suspension movement is generally less good in bumpy conditions.
So is it common to use more rear downstop when running with a oneway? I always have trouble getting my car to break straight when running a one-way, even though I check for tweak with a tweak station. InitialD already pointed out that I should check the downstops to make sure they are perfectly equal. Any other tips there? I should mention, that I do run very little break, so I'm not really hitting the breaks hard either


Quote:
In a small track with lots of corners you'd expect more downstop (less suspension travel) gives best results because the car responds quicker. Try to always keep the car "in the springs" so if the car is stationary on the table you can lift the chassis a little before the wheels come off the ground.
Thanks for the tips!
markp27 is offline   Reply With Quote
Old 11-20-2003, 11:43 AM   #1137
Tech Master
 
J_Longbrake's Avatar
 
Join Date: Nov 2002
Location: Columbus, Ohio
Posts: 1,234
Trader Rating: 20 (100%+)
Thumbs up

Great Info! Thanks Michael and Julius, keep it coming.
J_Longbrake is offline   Reply With Quote
Old 11-20-2003, 12:28 PM   #1138
Tech Fanatic
 
serpentracer1's Avatar
 
Join Date: Jun 2003
Location: Maryland
Posts: 777
Send a message via AIM to serpentracer1
Default

Thanks for the info yall gave us I was almost on track with the car and it was getting quicker and the handling was smoothing out really well .Cant wait for the 710.I see all kinds of possibilites!!
__________________
DAVE (THE SNAKE) Rasnake
Original Mimi Wong Clan. M.W.C. For Life
Associated B6D
Orion R10 Pro VST powered
serpentracer1 is offline   Reply With Quote
Old 11-20-2003, 12:29 PM   #1139
Tech Adept
 
Diesel Racer's Avatar
 
Join Date: Jun 2003
Location: UK
Posts: 227
Default

Quote:
Originally posted by lawndoggie
I totally understand! Who would want to wait 5 months!!
Check out Harmony and World Model. They'll both give you the same price. World Model is the distributor here in HK, where I bought the 705:
http://www.worldmodel.com.hk

but they might just ask you to get it from you LHS!
Thanks for the link lawndoggie.
Diesel Racer is offline   Reply With Quote
Old 11-20-2003, 01:56 PM   #1140
Tech Adept
 
Diesel Racer's Avatar
 
Join Date: Jun 2003
Location: UK
Posts: 227
Default Fuel tank

A question for Michael, Rene or Julius.

As a matter of interest is there any reason why the fuel tank wasn't reshaped on the 710 to gain a lower profile and hence a lower CG, much like the TM G4's, I know the throttle servo is in the way to the right and to move that out would change the polar moment, but surely the tank could have extended forward, it's just with the rest of the low profile design the tank sticks up like a flag pole which looks pretty crap.
Diesel Racer is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Serpent 705 J_Longbrake Nitro On-Road 4252 02-23-2015 12:34 AM
WTB: NIB Serpent 710 aN4rK1 R/C Items: Wanted to Buy 3 06-16-2006 09:23 PM
Serpent 835 JFCJ R/C Items: Wanted to Buy 3 02-20-2005 09:29 PM
Trade in Your Old Serpent 710 Parts for New Serpent 710 Parts fast_it710 R/C Items: For Sale/Trade 0 09-17-2004 12:27 AM
Serpent Impulse w/MT-12 and Serpent Starter box - cheap Solara R/C Items: For Sale/Trade 2 03-07-2003 03:01 PM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 10:46 PM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net