Over and Under or around the sides

[greenpower dude reloaded]

3/8" pitch. It's pretty OTT. There are certainly better types of chain that's for sure

[flynfrog]

Have you looked at cogged belt for drive?

[greenpower dude reloaded]

Certainly considering it.. our best guess at efficiency of this heavy weight chain is that it's about 92% efficient. I don't think it's unreasonable to think that we could gain a few percent with a different set up.

[tok-tokkie]

If you are looking into toothed belt drive be aware that there are different tooth profiles. Some years ago I was interested in belt drive for motorcycles & learned that the efficiency of the drives is dependent on the tooth profile. I don't have a record of the thread I was following then. Google gives me this: http://www.gates.com/facts/documents/Gf000289.pdf but that is all I have looked at right now.

[greenpower dude reloaded]

That looks really useful post Tok. Thanks for the heads up!

Just came across this pic the other day, I think it might be a good one for Laura's fan club!

[BreezyRacer]

In my experience cog belts actually use more horsepower .. especially if you use smaller sprocket setups. In addition the tensions required are quite high. Of course with your power limitations you could probably step down to a smaller size chain, not o ringed, and gain a little power that way.

Another great pic, BTW.

[greenpower dude reloaded]

Interesting, breezy. I had heard before that belts were more efficient, but I often wondered with belts if it were just the sound deadening capabilities of the compound used to make them that made them appear more efficient.

Well that's something to add to the wishlist I suppose;
Windtunnel/Somewhere to conduct coast down test
Dyno
Autoclave
Van

[BreezyRacer]

Just check out Gate's own data, and reference gear diameter. If you're running a 1 to 1 ratio with a large OD gear the drag may be equivalent to a chain, otherwise the way I remember it, drag is higher. Also the preloads required to get straight tracking of the belt are pretty high and require more weight, in the form of added supports and bearings. To be successful you pretty much have to mount to gears in a sandwiched bearing layout.

That's what I have found, albeit with a 100hp and 800 lb car with around 3 to 1 gearing. Chains rule, in my experience.

[Tommy Cookers]

A good old fashioned chain will have about 1.5% loss at each meshing of chain and sprocket

belts are good at being belt-like, but have clearly higher losses
(some belts or other types can drive round corners though)

O ring chains have a high friction independent of load, so will be particularly bad if oversized (until worn out)
they were designed for off road to keep out sand and mud, are nbg otherwise because they trap water and seize with rust

the best chain lubricant ever is oil/Molybdenum Disulphide additive ('Molyslip')
(thin it with light oil and apply from a can)

otherwise the best Teflon-loaded cycle oils are ok (many have little Teflon and/or it settles out and clumps)
(avoid off-road stuff, it tries to be semi-dry and is sticky)

so no problems ! ......... (unless you are doing 300 miles non-stop in the pouring rain)

[flynfrog]

That's what I have found, albeit with a 100hp and 800 lb car with around 3 to 1 gearing. Chains rule, in my experience.

r1 MINI?

[BreezyRacer]

That's what I have found, albeit with a 100hp and 800 lb car with around 3 to 1 gearing. Chains rule, in my experience.

r1 MINI?

Nope. It's a Formula 500 SCCA car.

[thisisatest]

you could go super-high tech f1-style and get a dlc-coated chain
http://www.kmcchain.us/kmcproduct.asp?p ... 3&ssid=692
these are bicycle chains, so 1/2" pitch of course. i have no idea what your torque requirement is, but there are a ton of options from the bicycle world.

[tok-tokkie]

I remembered who posted the thread about belt drive on a motorcycle so was able to find the thread. http://www.vfrdiscussion.com/forum/inde ... i-thought/ It is gates Polychain belt which comes in 3 pitches.

[greenpower dude reloaded]

So, I've tried writing this about 100 times over the last few months but what with a new (time hungry) job I've kind of let this just fall off the radar, which really isn't fair on you guys given the support you have offered, but I figured that as we'll be at Autosport International this weekend I ought to force myself to sit at my laptop for a bit.

So long story short, we had two races at Dunsfold and Goodwood (National Final) which rounded off what will be our final F24+ Championship Campaign.

We finished second at a horrendously wet Dunsfold park - where there is no shelter at all. By that point we had already maxed out the points you can take in to the final round (the season goes on your best 2 finishes plus the final) so it was more about taking points out of the opposition.



We finished second here but had a good race (and a very big spin which put a big grin on my face) so not a bad day all in all.

It was then on to Goodwood for the National Final, this was the biggest day in our very small time career but we were all very calm, very focused and didn't let the very critical failure of our datalogger in practice put us off our stroke.

We lead from the end of the first lap but slowly got caught and over taken shortly before the pitstop, we went on to finish second to a fantastic new team with a really great guy leading it. Not the result we were hoping for but who cares - it was enough to see us win the F24+ Championship.

I shan't bore you with any of the soppy emotions I experienced but I would like to thank you all for your support.







We shall be at the Autosport International show this weekend (public days only :/ ) please come a long and meet the team if you get opportunity we shall be on stand 9210 in Hall 9

[flynfrog]

Nice update mate. Also how do the flow lines on the wet compare to your cfd predictions?