dynoed my ds450

[ScottB125]

Finally got my DS on the dyno. This is a dynojet for cars. Baseline was 32hp/49 base. We did a back up run.....same results. Took the seat off and it pick 33hp/50torque. We then adjusted the tb and it picked up to 36/52.

Took the airfilter off and it didn't gain anything.

We've got the tb off and are porting it now. Will post if it lost or gained.

Scott

I'll post some pics in a few days. I took a few picks of the head...definate power to be had there.

[ScottB125]

ok, we ported the tb and did a run with the motor cool.......

39hp and 60 torque. This was with the seat off. I about fell over.

To confirm we did a back up run....37hp and 56 torque.

IMO, porting the TB adds some serious hp

We'll get some numbers with the seat on later

[GE4x4]

I don't know, but I can not see any 450 putting out 60lbs of torque. That's allmost double what other 450's are and the DS from what I have read did not sound like a torque monster.

[witech]

Its a car dyno so the numbers will be most likely be flawed. It should be usefull for tuning purposes though.

[ScottB125]

Yeah, I was mainly looked for gains from the baseline.

At the end, we put the seat back on and it made 36/52. As its been said, these motors want ALOT of air. I want to cut up the air box, but am worried about water getting in it.

What is cool, these are mods anyone can do.

I have a few other tricks we use on LS1s that I want to try.

BTW, my baseline mods were:

Rossier filter
pink wire cut
baffle out of stock muffler


In a week or two, I'm going to order a Motorworks exhaust and programmer, then put an A/F meter on it and see what it does.

[T-BONE#29]

THAT HP READING SUCKS THE ****

[Vade]

Those # are way off 41 hp/35tq is a more realstic number which is still high for what you have in it

[ds450]

ScottB125, how much did you port the tb? Or did you just smooth it out?



I dynoed mine with the baffle out, lid off, motoworks air filter, and pink wire cut and I got 36.5hp and i think 32 ft lbs of torque. And I removed the seat and it helped. Then I installed a rossier exhaust and didnt dyno it yet but it runs way too rich with the pink wire cut so im hooking it back up and getting a power commander. I cut 1" off the sides and back of the air box and it helped.

[keglassg]

those high number dont suprise me, especially the fact that it has almost twice the torque of the other 450s because the yamaha specifically doesnt make hardly any torque until it hits the high rpm range, its like the old 2-strokes almost, where as the DS makes consistant torque in all the rpm ranges. these numbers may be a little high, but i doubt it.

[ScottB125]

When you pull the TB off, you will see it has an edge by the throttle blade. Grind that down and blend it in. We used a sand roll on the rest of it, mainly just smoothing it. We narrowed the throttle shaft too. Also check that your throttle blade is opening 90*. That helped out quite a bit too.

Important...do not cut into where the throttle blade seals. You can port right up to that.

After we did this, mine idled a little high, so we had to pull the TB back off and adjust the idle screw.

After it was said and done, the motor is alot more responsive.


I was reading in another post about a 50mm tb avail. I would like to try one of those or get a new butterfly and port my stock one out larger.