markp27

Thanks for the praise, but I'm just cataloging the excellent input given by the guys here. Also the same sort of questions come up at regular intervals and poor old Mr D has to go and repeat himself I was afraid in his old age he'd start forgetting what he'd already said

For whatever reasons, the Serpent 705/710 forums have been and are a real little community where we get help and comments not just from us hobby drivers, but also the designers and team drivers. I thought it would be a shame if this information became "lost" due to the number of postings.

I'd like to try and maintain the FAQ and post it at regular intervals, so that we have a knowledge base which can be quickly referenced for common and tricky problems.

Lets see how it goes

Mark.

InitialD

See what good things come about when you have too much time can do to you?

Hey Mark, that's a good compilation. Even I can't remember so many things that were written by myself and others. Having them consolidated is very useful. I think that is what Sow&Steady is wanting to do... But of course on a larger scale.

Perhaps we should put this to Rene or Julius and ask them to append it to their manual !

InitialD

Diesel Racer, the Centax requires very small and precise measurement requirements which affect the clutch greatly.

If what you've decribed seems to be the problem, you should only be loosening the spring pre-tension nut. Not tightening it. Perhaps your clutch "problem" could also be compounded by your engine still running rich.

Anyway, are you measuring the 0.7 mm clutch bell / clutch shoe gap with vernier calipers? Take it out now and measure it again. I once had the problem recently. What I measured turned out to be more after running the car after a few times. No, not because of clutch shoe wear but my guess is sometimes the clutch parts needs to "settle in". I wanted 0.4 mm and it turned out like 1.0 mm if I was not mistaken. So take it out and measure it again. A smaller gap like 0.4 or 0.5 mm would help plus loosening the pre-tension nut.

The above should cure the problem. If you want a more RESPONSIVE clutch, then follow the instruction Mark has compiled.

InitialD

You're right ! I'm not getting any younger !

Cool ! I remember that was what they tried to do on the old Serpent Impulse thread when the non-HPI forum was up and running then ! After a while, one of them would summarised what has been discussed and posted it again in a concise form. Then the other forumers could add and append was was correct, accepted and understood. Good Bless that forum's soul !

cyba888

When I brake my car turns to the left. How do I adjust this. I forgot Julius had a link to this problem but I forgot.
Lets say if it is the springs that you need to adjsut then wont that tweak your car if you do the lifting method?

markp27

This is because your car is tweaked.

Check the "Sequence for tweak/droop/sway bar" in the FAQ I posted and then use the lifting method to set the springs correctly.

Cheers, Mark.

InitialD

Julius suggested the lifting method which eliminates tweak. This includes readjustment of the shocks to get equal left and right tweak.

Something related to this, I noticed a few peculiar things about the car this morning when setting it up. I guess some people like clmbia45, Pyramid and Goldfinger have already brought this issue up before and related their account but here's what I personally found...

Firstly, when I set rear droop and making sure left and right were the same on the droop blocks (reading taken from the lower knuckles), they lifted uneven (right was lifting earlier than left) when I did the lifting method with just the rear tires attached (new equal size tires, no shocks and no sway bar) and with the front end on a solid block. I made it equal left and right by limiting the left rear droop and making sure left and right lifted at the same time. This was still without shocks and sway bars on.

Next, I fitted the rear sway bars, without shocks and with the same equal sized new rear tires. Again the right side lifted earlier than the left. It looked like the right side lower arm could not fall freely so that the droop screw would hit the chassis. Took out the rear sway bar and left and right lifted the same. So it must have something to do with the rear sway bar then... I proceeded to lengthen the right rear sway bar linkage. Did not check how much longer I needed to make but it was probably like 3 to 4 mm more than the left linkage. So the rear was lifting equaly left and right with the rear sway bars on and without shocks.

Fitted the shocks together with the rear sway bars on and did the lifting method again. Slight minor adjustments to the rear shocks were made to make sure left and right lifted equally. All this done with the front end chassis still supported on a solid block.

Next, I did the front end. Still have not used the front sway bars yet so setting the front tweak was simple and straight forward. Did it like what I did for the rear with now the rear end chassis supported on a solid block. Front end lifted equally left and right with and without shocks.

Just to satisfy myself and perhaps also "justify" the tweakstation purchase and put it to "good" use , I put the car with one end of the chassis on a solid block (to ensure that the front part is not hanging on springs) while the other on the water bubble cantilever. Did it for the front and rear and it was smack on the middle.

Next, I put all 4 wheels with shocks (no solid block on either end) on the tweakstation and see what the bubble tells me. Balanced front and rear side !

Sorry for the long story or if it makes for any interesting reading but I just had to push this outta the chest !

Sow&Steady

Shhh! Learning html is easy, PHP is another story but Perl and all that ... well ...

Sow&Steady

I think you've got it nailed. Its a little bit of a long process for my liking but if I ever see that the track I'm about to race is flat, technical and with quality tarmac, I'd go for this full process.

Have you tried testing your car going round in circles a few times both clockwise and anti-clockwise with constant low-mid throttle and compare the paths?

Try it next time you're on a flat piece of tarmac after a good tweak. Then blip your throttle (to full power if you're comfortable) during the circular run both ways ... you'll find the results interesting. I do this a lot and adjust according to the track if I think there's a particular spot I'd be eyeing the "competition" for a quick fly-by.

markp27

Would this have been covered by the following Julius method?

- Connect the sway bar. Set droop using the screw for te right side of the suspension only. Measure on the right side.
- If the right side is correctly set fo droop, use the cam of the sway bar to set left side droop. In theory the left side droop should be set a fraction lower to compensate for play in the sway bar (no more than 0.2mm so it's not really important).
- Then by sliding the sway bar in it's holde disconnect the sway bar.
- Now set the left side droop screw to the same droop as the right.
- Reconnect the sway bar.

Now droop is equal and the sway bar is aligned.

Then set tweak using the lifting method.

InitialD

What Julius wrote above is how to set the front droop with the front sway bar connected.

InitialD

It's a long process alright if you take the somewhat repeating steps of putting the car on the tweakstation for double checking purposes just so that it may be put to good use !

I think just the lifting method would suffice. Just wanted to satisfy my curiousity and check my findings thoroughly while I was at it !

Anyway, doing this goes a long way especially if you're running one way front where any slight small tweak will rear it's ugly head when you apply brakes !

Ummm, what characteristics of the car you hope to look for and achieve by doing this? Better / sharper cornering radius?

Diesel Racer

Hi D, I've just been working on the clutch and got it sorted as you say by releasing the tension on the spring, trouble is I think the clutch cuts in too soon, but as soon as you increase tension it starts to slip. This clutch seems a lot more sensitive than the Centax II, I'm thinking that maybe the spring is a bit weak, but when you dial in more tension it becomes coil bound, I believe the Centax II spring is slightly harder so may give that a try.

Thanks

Mark

InitialD

Hey Mark, yes the Centax coild spring that comes with the 710 is softer than the one that came with the Centax II (1.7 mm versus 1.8 mm diameter). In fact, that's the spring that came with the older Centax I. I guess the setting is more sensitive due to the lighter internal parts of the Centax 3.

markp27

I'll modify the FAQ and add your method, too.

Cheers, Mark.