It is hard to say what will work, since you need to test the result on a dyno to see what power improvements it makes with deferent setups.

Seat in the pats will not show where you gaining or loosing as well as a dyno.

 

My son works for a Bomb dealer and rides everyday.
He is very good, but when the discussion leads to, well what do you think,
then it is time to do dyno testing.
If the final results show that the data is worth sharing,
then only with objective evidence will the facts be shown.
I live in a city so testing requires loading and driving somewhere.
There is only one dyno in the state of Wisconsin and it is over 2 hours away.
So when I feel I have something that will add value to the stock carb,
I will spend the time and money to get the data.
I just wish there were more members interested in improving the stock carb.

 

I am trying to arrange a stock DS, so I can test all these findings on a dyno to get the facts. Then I will have proof to show what mods work and just how much they increase power. Making dyno time is easy. The hardest part is finding a stock DS that is still new and untouched, since most of the guys mess with them before I get my hands on one. Most of the time I also did the mods and if the seat in the pants showed it made an increase in power we sort of stuck with it for the next DS coming in.

 

My sons 05 has been altered. It is stock in the sense of stock carb, cam and piston.
When I am done with testing the carb, I want to show a dyno run to show how much power can be gotten out of the stock components of the DS. All this on 92 octane fuel.

Too many guys start to change parts without trying to find out how much power is in the stock components. Dealers of course love to sell parts and when that part isn't enough, they sell you somemore parts,etc. I see several guys putting lots of money into there motors, and when they post their dyno runs, the cost per horsepower is crazy. Several of them have only gained 4-6 hp and have put $2500 into their motor.

Randall and Eric are great guys and have done alot of work on the DS. I thought that most people that ride quads are looking for a fast trail motor, too bad most efforts are spent on drag only motors.

 

I was told to remove the lid, gasket and the snorkels after I installed my TM45. Although, I think I'll remove the entire box since I only run the Dunes.

 

I agree since you are running a flatside carb. Or you could be the first to try to control the air with a modified airbox. Buy a kit like the one's on Ebay and save your airbox for future development.

 

Oldmanracing I havent run stock class for a few years now but there is still lots of testing that can be done on the factory carb. 2 hours is a very short drive for some real world dyno data!

Be absolutely sure to bring an unaltered stock carb with you to compare back to back results with your modified stock carb so you can see the exact differences between the two. And dont even go unless you have some flat track tires. If you run knobbie tires and a carb mod makes more torque for instance the dyno graph can show less torque because the knobbie tires will slip.

What main jet are you running?

 

Stock emulsion tube:
Mikuni 175 Lid On
185 Lid Off

Modified emulsion tube:
185 Lid On
195 Lid Off



I have been layed off for 5 months so that is the major reason for not dyno testing.

 

5 months...ouch. Try lid on a 150 main and see how it pulls on the top end.

 

150 WOW thats a lot lower than stock, But I ll take your word on it, your the pro not me.

OK Ill bite... Ive been following this post and its very interesting I applaud you all for livening (sp) up a beat up topic.

I been all over this topic B4 (as freeze knows) and when I ran the stock carb I had my best results w/ the lid on why ? at the time I had another DS to run w/ side by side. only diff. was he ran a fmf slip on w/ dyno jets, me stock pipe, jetting and supertrapp end cap.
I constantly lost in a drag race by 3-4 bike lengths when I took the lid off whether I rejeted or left it alone. I did not try the filter on the breather tube trick though. now I put the lid on I pulled him by 1-2- bike lengths. so I was a firm believer in lid on!!

also he had a tach on his DS and when he was at idle and in neutral he reved it up hard it would rev quicker w/ the lid on than lid off it was very noticeable by just watching the needle. grant it this was just removing the lid and putting it back on no other changes. it was just funny how it would rev slower w/ lid off than on. just a observation

Now I think what Oldmanracing sad about the emulsion tube losing inertia at the start of a race is very real. this was happing to me and I couldn't catch up. when I raised this other DS .
I think your all over it OMR. I think w/ more testing Freeze and OMR maybe will get some thing working w/ the lid off or air box totally off. time will tell

now there has been post of guys in higher elevations having being able to pull a higher gear up hill w/ the lid off. I believe this totally, It could be the higher elevations need to breath more than sea level I don't know. If it works do it!!

until you get on the dyno you might run side by side w/ another DS or raptor ? some thing that stays close to you in a race and compare results w/ each run whether your gaining or losing.

but my money is still on the dude w/ all the titles under his belt and what he would recommend .... "lid on" Dude

I know this is just adding to the debate and not really solving anything but its JM2C hope this helps any one reading.
Later