Chris' Optima rebuild
 

Well, the postman delivereth my Optima. I believe that this is an Optima turbo, but I will ultimately build it as an original Optima, but am not intending to rigidly stick to only Opti parts (ie, I am happy to use the turbo shocks etc).

It doesn't look in too bad nick, but the tyres are a bit perished and the usual things like shock collars are broken. I also note the top deck is quite badly warped as is the rear shock tower

Still in the box - does this count? :)

The chain looks a bit ropey so I may have to look at whether I can do something about that

Drive train doesn't run smoothly at all. Not too worry thought as I plan to fully strip the gears and diffs down anyhow

That chain can give one some headaches, I remember the time it took to straighten the bent links on my Turbo Optima, which also came with a battered chain. Take you time, what worked for me was to keep the wheels mounted, pinion removed, so there is the least resistance from the transmission, so it's easy to feel any hiccups in the drive when you slowly push the car forward.

Screw kits
 

Does anyone have experience of
http://www.rcscrewz.com/product_info...roducts_id/482

The screws are not in great shape with some stripped heads and a few missing so wondered about a full new set. I can't see what is in this kit and wondered if anyone knew?

Other suggestions gratefully received

Chris

After not having luck trying to track down a new chain, I had a go a repairing the existing one but there were at least 11 quite badly bent / warped links so it will be a slow job.

I did take a punt on a Kyosho Rocky 4wd chain as they looked similar - what I found was that the chains are identical, but require 16 additional links so I bought another, extended one and hey presto, a new Optima chain in place.
I mention this as there seem to be more new Rocky chains out there for sensible money

Just ordered 2 sets of those RC screws, fully satisfied.:)

Just to give an update, following advice from many sources (mainly on here - thanks to everyone) I decided to switch to a belt drive so I obtained the option parts for a front and rear ball diff and fitted them straight into the gearbox cases. The pulley wheel kit isn't really needed and the belt runs super smoothly.
Following some threads on the shells from Kamtec and Marwen, I tried them but they are a bit short (albeit lovely shells) so I spoke to Steve Haskens (Penguin shells) and he said he can do them the standard size as he has a mold which has been corrected.
His shell arrived and is a lovely fit - will now have to post some images of my attempt at a box art paint job!!

Nice to find a repro body the correct size, often the length is slightly off, on one repro company even more that slightly. Does Penguin also supply window masks? Masking windows still is a pita when you paint.

It didn't come with window masks, but it wasn't a big issue - I must admit, I have never had masks for any window!!

I have painted one myself so I can at least have a shell on it, but will get one pro painted so it can look as good as it ought to!!

Off the pace?
 

So the Optima had its first run out today. Batley included a vintage round of heats in today's meeting and though all the other vintage cars were newer (a stunningly quick optima mid, a few re-re rc10s and a couple of others) what was noticeable was that on the straight I was half the speed of the others cars. I've got a 17t hobbyking bl motor and I checked the ESC settings to make sure I was not running at low power etc, but I was amazed how much off the pace I was. Do you think an optima (running a belt) would take a 13t motor ?

Might be the motor, but it could also be you are not running a large enough pinion to take advantage of the higher torque of a 17T motor compared to a lower turn one. What pinion are you running?

I hadn't even considered pinion!! I must admit, I don't know off top of my head so will check when I can fight my way through childrens Christmas presents to get to it. I'm not sure what options I have as I recall that the old optima onions are a different size (pitch) to current ones. Will have to rummage in my box of old bits...

Just thinking about it, I seem to recall it being a 13 or something like. What can I go up to?

Hi Chris,

my Mid was running a 10.5 Orca Motor with a 20T pinion which seemed to be perfect.

When I spoke to Rob with the white Lazer ZXR, he was running a 6.5 motor (can't recall what make) with a 20T pinion. There didn't seem to be much if any difference in power/speed down the long straight.

The regular Optima has a different gear reduction, stock pinion is 14T for instance, while it's 20 or so on the Mid. With a 14T on the Optima, you get total reduction of 8.8:1. The smallest pinion listed in the Mid manual is a 15T and that gives a total reduction of 13.04:1. So you can't directly compare, you need to look what gear ratio you have on the Mid with a 20T, and then look at the Optima manual for the matching pinion teeth count.

@Chris: The Optima uses Mod 0.8 pinions, which tends to be very close to 32dp, I've been told. The Mid uses mod 0.6

I'll say!! It was amazing to watch it go around the track.

My concern was the lack of slipper in my optima and not wanting to shred the gearbox. I will see what pinions I have and then look into a couple of 32dp pinions once I know what I have. I saw Rob's lazer going round, but it was more your mid that impressed as it is almost as old as my optima. That isn't to say the others didn't impress, just yours seemed to drive and handle like a modern car, while only a couple of years advance over mine

The Mid has one big advantage over the regular Optima, the different weight distribution. Also there are more positions for fixing the tie-rods, to affect camber when the suspension is getting actuated. Also tires can make a big difference in handling.

Just realised I have no piccy of my finished Optima on here. So, here it is - shell courtesy of Mike Parker - Number 5 designs

Haven't sorted pinion yet, but not planning on much racing at moment so there is time

Looks amazing, very close to boxart. What did it cost to get it painted this way?