|
|
Post by teddy554 on Dec 31, 2012 19:48:01 GMT -5
look for options on carb that will use oil pump and fit stock intake i was leaning on the phbg from your 90cc build and was checking pricing and with choke cable and jet kit i am looking at about about 130 at racingplant was hoping to spend under a 100 bucks guess that wont happen i was working on my jetting today and started at 95 then drop to a 90 then drop again to a 85 and still fell i can go lower. I had to screw the idle screw all the way in to get my highest idle, so does that mean i should go lower on jetting. It didnt have much power only drove it in a little circle. think the crab is the issue, its different then the ones that usually come on Chinese scoots it has a lot of play in the throttle and i have to turn more then a quarter turn to get any action from it. here is a video with the 85 the 90 was bogging and shut down the motor  |
|
|
|
Post by skuttadawg on Dec 31, 2012 20:50:19 GMT -5
What size mm is the carb ? What exhaust ? I run a 110 with a 72BBK Uni and MMG pipe
|
|
|
|
Post by teddy554 on Dec 31, 2012 20:52:24 GMT -5
its a 90cc with type r exhaust and a stock 17mm carb and a nock off uni filter
|
|
|
|
Post by skuttadawg on Dec 31, 2012 20:52:49 GMT -5
|
|
|
|
Post by ryan52 on Dec 31, 2012 22:05:58 GMT -5
i have a 90cc well its now a 110 i believe 45mm stroke 54mm bbk, and i run 19mm carb with tuned pipe stock air box and a 95mj and its on the money with the mix, i live in Michigan tho
|
|
|
|
Post by skuttadawg on Dec 31, 2012 22:13:47 GMT -5
the Power Kits for 70cc come with a 21mm so a 90 would need even larger
|
|
|
|
Post by ryan52 on Dec 31, 2012 22:55:58 GMT -5
i read up on 90gtverts posts about diff carbs sizes with 90cc enigine stock airbox and pipe and i choose to use the 19 because not only did the engine stay as cool as all the others but it had better performance than 21mm-28mm. and he was very very thorough on his work. also the mpg was better by far!! than the 21-28.
|
|
|
|
Post by skuttadawg on Dec 31, 2012 23:00:45 GMT -5
Yes sometimes too big of a carb makes you leaner and does not help you in performance as a smaller carb
|
|
|
|
Post by ryan52 on Dec 31, 2012 23:27:26 GMT -5
i think the 19mm carb with 90-105mj is sufficientc for a 90cc. you cant really go crazy like you can with 70cc mods. which kinda sucks. malossi does have a sport 57.5mm bbk which is on my list
|
|
|
|
Post by teddy554 on Dec 31, 2012 23:33:13 GMT -5
i got a stock carb on now with a 85 i feel like it could go lower not sure will find out tomorrow but my 70cc doesnt run that low of a jet i cant understand why the 90 with pipe and open filter want to run a lower jet maybe the foam filter is more restrictive then the paper ones
|
|
|
|
Post by skuttadawg on Dec 31, 2012 23:38:18 GMT -5
Stock oil pump ? I would get a Mikuni oil pump and throttle cable part # 159-26 which I just got from Greg
|
|
|
|
Post by ryan52 on Dec 31, 2012 23:43:23 GMT -5
usually the 70cc need bigger carbs because ther running rpms are higher and at 55mph with 70 you'd expect 10000-11000 rpm...90cc at 55mph expect 8000-9000
|
|
|
|
Post by skuttadawg on Dec 31, 2012 23:45:42 GMT -5
Yep mine hits 9,000 at 50 but tachs up to 11,000 as to why I ordered 8g Dr P sliders instead of running 5 g rollers to have the RPMs down at top speed and better MPG
Airfilter or airbox and exhaust have a lot to factor with the jetting
|
|
