Author Topic: 50cc Sidecar Scooter  (Read 47220 times)

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Offline sofadriver

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Re: 50cc Sidecar Scooter
« Reply #60 on: April 19, 2016, 03:37:59 PM »
9:1 final gear ratio, CVT primary (2.45-0.85:1), 90-10 tires

so whats your pie-in-the-sky speed goal? You can figure your RPM goal from that and tune the pipe
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)

Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #61 on: April 19, 2016, 10:40:05 PM »
I'm going 58 at 9000rpm and want to go 63 with the 50cc engine and 75 with the 70cc engine.
Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931

Offline sofadriver

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Re: 50cc Sidecar Scooter
« Reply #62 on: April 19, 2016, 11:23:08 PM »
C'mon, Rev, you gotta set loftier goals than that !

How about 70 and 80.  :evil:

Believe. BELIEVE !!
Mike in Tacoma

"aww, what the hell - let's just do it".............

Bike #833
100cc A/G, A/F and APS/G (in 2019)

Offline rgdavid

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Re: 50cc Sidecar Scooter
« Reply #63 on: April 20, 2016, 07:24:16 AM »
That should be doable,
Have you measured your squish ?
How large is the squish bande,
How many cc in head ?
Is piston flat or domed ?

Can you make a port map of the cylinder to show us ?


Offline 808BMW

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Re: 50cc Sidecar Scooter
« Reply #64 on: April 23, 2016, 07:50:15 PM »
Wow, had to register just because this build is so cool.

Not too familiar with flat racing but pretty well versed on these scooters. I'm assuming the course is very long so acceleration isn't much of an issue? 9:1 is ok on a 50cc but a bore kit can easily push 8.4, maybe even 7.8 or even taller. They have primary gear kits that are fairly easy to swap around (the secondary kits need a press so it's not really a field swap).

Have you played with the rear pulley center spring, clutch springs, and variator weights? Once you make too much power the belt can't ever reach "top gear" so transmission tuning really helps.

Is your boost port (where the rod is resting while your motor is apart) matched to the cylinder? Not really viable if you plan on switching cylinders but once you are dedicated to 1 motor setup it's good to do.

The best pipes to emulate would be a scorpion/phongeer/arrow. Malossi is highly regarded for their cast iron cylinder and counter weighted crank, but the exhausts aren't the top choice.


Best of luck and I can't wait to see how fast you can get this thing going!
« Last Edit: April 23, 2016, 08:00:19 PM by 808BMW »

Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #65 on: April 26, 2016, 11:19:59 AM »
Tried a new pipe and picked up but it a bit strange on jetting. It is a Polini Corsa race pipe.

Using the same 98 jets it ran previously 54 (57.9 with fairing), it ran 57.4 so a quick gain already, and it was very responsive. This is with the 21mm OKO. I put in a 102 jet and it acted very rich before hitting the power band, 4 stroking, but when it hit, it picked up and ran 57.9. I put in a 105, the pre-power band got much worse and almost wouldn't get on the pipe, but when it hit, it bumped up and ran 58.4. With the fairing that should be 62-63. So, it acts like it wants more jet, but has trouble getting on the pipe when I give it jet.

As a note, the clutch is engaging about 5200 and then peaking about 9400 before the CVT pulls it down. It runs top speed about 8800. I run a yellow Malossi center spring on a stock clutch housing with the lightest of the Polini outer clutch springs, giving me the 5200 engagement. It has a Ruckus Malossi variator with 5.6g weights.

I have not opened up the block for the bigger boost port as I was planning to go back and forth between the 50 and 73cc jugs, but I know this is one more piece holding me back so I will probably port it after this weekend in Ohio and see how it likes it.

I tried to part throttle it and see if I could get it on the pipe before going past 3/4 throttle and getting into the main jet, but it didn't have enough power to get up there. What is your best advice? Lower the needle or try a bigger one? Or???

Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931

Jessechop

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Re: 50cc Sidecar Scooter
« Reply #66 on: April 26, 2016, 12:20:44 PM »
I would drop the needle.  You almost need an additional fork circuit like a thunder jet

Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #67 on: May 01, 2016, 11:56:37 PM »
Made 3 passes in Ohio Friday and ran a best of 59.7. Not half bad. Really looking forward to running Saturday morning with cold air and a slight tailwind, but an unfortunate incident on the track put that to a close.
Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931

Offline mtkawboy

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Re: 50cc Sidecar Scooter
« Reply #68 on: May 02, 2016, 12:28:16 PM »
There probably isn't room on that carb for a Thunderjet

Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #69 on: May 02, 2016, 02:05:21 PM »
The Thunderjet looks interesting.  May be worth a try and I think I can make it fit.
Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931

Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #70 on: September 07, 2016, 02:00:20 PM »
We have the turbo up and running good and are loading up to head to WoS leaving tomorrow! The goal is to get my pop a record (at 82 years old). as long as we can make two passes on the open record we will meet that goal, then we can really start playing around!

Current incarnation is 72cc and running in SC/BF100
Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931

gkabbt

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Re: 50cc Sidecar Scooter
« Reply #71 on: September 07, 2016, 02:39:00 PM »

Good on ya, Daryl! REALLY COOL to do this with your Dad. Good luck and keep us posted on how you guys do.

Gregg


Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #72 on: September 11, 2016, 12:18:40 AM »
Couldn't ask for a better day. Beautiful weather and just the right size crowd. Got through tech and went to make some runs on the short course and make sure all works well. Zero line and I made two passes easily at 49 and 48 mph. We changed drivers and put dad on the bike. He had never until this moment ridden this scooter or anything with a sidecar. He cruised through at 30, but with no problems.
We went to the long course and got in line ( they only do SCTA records in the long course). We got him ready to run and there was a huge crowd of people taking pics. Really cool! He made a great pass at 39 mph and we are in impound. 
Tomorrow morning we go for return run😁👍😁👍
Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931

Offline wickedwagens

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Re: 50cc Sidecar Scooter
« Reply #73 on: September 20, 2016, 04:19:00 PM »
I was in tech around the time you were going through.  It was good to see the little scooter out there.  Very cool!
1968 Volkswagen Karmann Ghia
G/CFALT  106.643 MPH  8/2016    G/CGALT  113.131 MPH  9/2016
G/CBGALT  169.462  MPH  8/2021    G/CBFALT  146.715  MPH  8/2017
G/CBGC  158.242  MPH  9/2017   H/CBGC  94.334 MPH  8/2018
H/CPRO  93.383 MPH  8/2018   H/CBFALT  101.282 MPH 9/2018
H/CBGALT  120.591 MPH 9/2018
Top Speed 170.726 MPH
36hp VW 100 mph club 9/2019 102.319 MPH

Offline revolutionary

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Re: 50cc Sidecar Scooter
« Reply #74 on: September 20, 2016, 09:53:45 PM »
My dad called when we were driving home and told us he is ready to bump his record next year 😁👍
Breaking Wind #9614
  ECTA Record AA/BGALT 214.8
  SCTA Bonneville PB AA/BGALT 237.4
Breaking Wind "Spirit of Effluvium" #451
  SCTA Bonneville Record SC/BF100 48.931