First let me thank cabinfever for the idea of direct air...i put the finished product on my 50 slant...i dropped the neddle setting down a notch and with the air intake it has smoothed out my start and added to my top end by 2 mph...and its smooth...i took my large expansion pipe off and went with deul exhaust 13.95 plus shipping...smooth...ha...thanks...enjoy...Dennis
direct air and duel exhaust...
- Thread starter drhofferber
- Start date
you are welcome,its all about trying new ideas out and to get a smoother running bike.
i origionally did this to relocate the airfilter since i didnt have room for one on my roadmaster sx sport(my last build) and it did so well that i kept using it on my new bike a scwhinn delmar cruiser even thou i now have room for a fullsize airfilter in stock location. I am looking to do a redesign on the pipe and filter for even more performance and i will be doing something to quiet down the clutch and cover. plus i need to clean out my muffler sometime(darn power robbing black cat muffs).
i origionally did this to relocate the airfilter since i didnt have room for one on my roadmaster sx sport(my last build) and it did so well that i kept using it on my new bike a scwhinn delmar cruiser even thou i now have room for a fullsize airfilter in stock location. I am looking to do a redesign on the pipe and filter for even more performance and i will be doing something to quiet down the clutch and cover. plus i need to clean out my muffler sometime(darn power robbing black cat muffs).
get rid of that black exhaust...cuts power down alot....as far as the sound from the clutch cover, i bought some of the krylon rubber paint and sprayed it in the inside of my covers...3 coats...works good...catch you later...Dennis
AHHHHH!!!!!!!!!!!! the bad memories!!!!!!!!! i did that with my air filter, and a rock got in, all the way into cylinder, and took a good sized chunk out of it.
well i have two screen filters as you can see in the parts...and if it does happen it would give me an excuse to change it to a 80cc...by the way how did it perform while it was working...thank you...Dennis
thanks pablo...it is smoother and better top end...just having fun and enjoying the hobby...working on a tensioner...using amisol 80 to 1...ha...buying my own amisol stickers...ha...new exhausts...things that a good hobby should do...thanks for the reply...i.ll keep everyone posted on the outcome...Dennis
It's possible as you approach 40 mph that the effect increases. Plus you are avoiding the heated air from the engine cooling fins.
Re: Respuesta: direct air and duel exhaust...
you remember the tornado...they make a knock off of it for 10.00, i'm going to buiild another with it inserted...smoother the better...for some reason i'm preferring smooth over speed...this is just a 50cc and by taking off my large expansion pipe and going with the deul exhaust its slower,not much,smoother and better to get along with...my 80cc cruises great...a different world...fun is the name of the game...thanks for the reply...Dennis
Pablo...i'm going to do one a little different for my 80cc...it cruises at 35mph...i'll post it when its done...the 50cc cruises at 25mph, it goes faster but why....the 80cc, ha there is a Why...ha...thanks...Dennis
i would of like to put it lower like your bike but i mounted the engine high..this bike is a constant work in progress...thanks for the compliment...sometimes thats all we got to keep going...hey!...Dennis
It does have significant effect, little to do with speed of vehicle though. As I mentioned in a previous thread aircraft people discovered blown or ram air does not increase performance significantly with out major modification to the carb. However removing restrictions such as air filter does appear to boost power slightly. It does this by leaning out the mixture big time. Just like raising the c-clip. Not always a happy ending.
My point was dust (silcon dioxide, most common abrasive known to man) will soon bring an end to whatever small benefit may seem apparent by removing the filter.
FYI tuning the length of the intake can result in real world improvement.
Xlite..thank you for your concern...i did lower the clip one notch and may lower it one more...and pretaining to the filter ...its still there...this is the same air filter that came with the carberator except i have changed the cover...it use to have louvers...now its solid with a hole and insert for the hose...everything is the same..just another experiment...i'll keep you posted...Dennis
i have a 48cc and it does 35mph.
im not trying for ram air,its just my engine likes to breath.
i now have a thin filter on the end of the pipe.
my pipe is not facing the front of the bike no more,it is now at a angle facing the bottom rear of bike along bike frame.
ram air? maybe not. but with 35mph @ 180-200mpg i must be doing something right or i just got a good engine.
im not trying for ram air,its just my engine likes to breath.
i now have a thin filter on the end of the pipe.
my pipe is not facing the front of the bike no more,it is now at a angle facing the bottom rear of bike along bike frame.
ram air? maybe not. but with 35mph @ 180-200mpg i must be doing something right or i just got a good engine.
cabinfever...what notch do you have your needle set...and where did you get your engine from...same carb..factory...ya i bought a nice cone filter from kragen with a 1 inch hole...i elected to go this way...gets alot of air..i notice it in the morning...once it gets going than the trootle starts working properly...probably could go down a notch, but i'll wait...all i no its alot smoother and less work on my part...this engine is a slant 50...its always been rough...its getting alot better...what do you notice the difference when you changed the direction of your air tube...i'll be doing alot of experimenting..thats the fun of the hobby...don't know if its right unless you try...hey...thanks for the reply...Dennis
I was just warning about the dangers of running with no filter at all.
If you still have the original foam then there is no risk. No dust is getting in and it hasn't leaned out much. But I doubt there is any ram effect due to that filter and the small opening up front.
I think if one had a really wide mouth (i.e. 12") pointing forward and no filter then ram effects could occur at high speed. This would cause major leaning which might be harmful. Just speculation.
2 strokes are funny. Turns out changing the length of the inlet tube can have surprising effect on power. I haven't experimented with this myself and don't know if the stock inlet is optimized. I believe adding tubing like you did could increase power if the original path was too short. I don't know what effect having the foam still in place would have on this.
FYI Moving the clip has little effect on mixture at full throttle. To really change ratio you'd need to drill out the jet. If the foam is still there I don't think it's necessary to do that. These are a little rich from the factory anyway and IMO those covers with the 4 tubes pointing down are too restrictive (you had the type w/louvres). They act like a choke. Maybe the louvres are less restrictive.
Getting rid of that stupid plasic cover with the tubes is a good idea. I replace the cover on some of mine with safety wire to hold the foam in. On others I cut off the bottom half with the tubes. The remaining top part still holds the foam. This gives barely noticeable increase in power. Not much, a little over 1mph average. And my plug shows slightly leaner.
PS I discovered this trick accidently because the engine will not fit a Magna Glacier Point with that stock cover on. Took it off, put it back, took it off again, put it back... There was no doubt, a little more power.
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