My numbers are: 40/76/35/84/29/86
The thoughts behind them are rather long winded, so I'll hide them for those of you who don't care.
1) Emulate example lines.
Growlithe/Arcanine has differences of 35/40/35/30/30/35. When the same differences are applied to Syclant, Syclar's base stats look like 35/76/35/84/34/86. If you do the same with the differences for Joltik/Galvantula Syclar has 50/86/60/74/54/78 for base stats.
2) Average the emulations.
The two sets of base stats average out to about 43/81/48/79/44/82.
3) Get the base stats the correct distance from multiples of 5.
Most Pokemon maintain the distances from multiples of 5 in their stats when they evolve. The averaged stats have distances of -2/+1/-2/-1/-1/+2, while Syclant's are 0/+1/0/-1/-1/+1. If you shave off stats to get them to the correct distances you get 40/81/45/79/44/81.
4) Look at the thing.
I personally can't imagine Syclar physically attacking anything, so the fact that its attack was higher than its special attack just seems wrong. It does evolve into Syclant though, so I'm not going to kill its attack. My solution was to decrease its attack by five and increase its special attack by 5. This leads to a spread of 40/76/45/84/44/81.
Syclant's defence is not higher than its HP. 40/76/40/84/44/81.
Syclant's speed is it's highest stat. 40/76/40/84/44/86.
Syclant's defence is 6 points higher than its special defence. 40/76/40/84/34/86.
At this point the spread has a BST of 360. 10 points less and it'd be on par with Growlithe, which is where I want it to be. Take five points out of defence and special defence for 40/76/35/84/29/86, with a BST of 350.
For those wondering why I only used Growlithe/Arcanine and Joltik/Galvantula as examples here's why. Of all the example lines that popped up in the overview only those two work. Anorith actually loses 30 base speed when it evolves, so factoring it into the equation leaves the average stage with 105 base speed, which is insane. Karrablast/Escavalier leaves you with the same problem, albeit on a smaller scale, because it maintains its base speed when it evolves. Finally, Shelmet loses defences when it becomes Accelgor, which makes Syclar altogether too bulky.