Re: Vespa + HPI Mini Rotor

Max (ツ) /
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Lots of math this morning

TLDR = after lots of number crunching, this kit will want 2.4mm BTDC when the timing marks align (if they were still there) and I have a plan of how to set the timing

Annotation2020-03-22104852.jpg

I looked up the static timing suggestion from the Malossi manual for the DEPS kit and they like 19 deg BTDC

Next step was to try to graph (as best I can from the low res HPI picture) what the curve is on the Mini Rotor. My RPM will likely top out around 10k the way I'm setting this guy up. I took an average from 0-10k rpm and it was 19.5 deg BTDC. I then shifted the HPI curve -.5 deg to approximate the best timing curve for this cylinder.

The HPI firing marks (if i still had them) align at max advance which with my adjusted curve is 24.5 deg BTDC. Using 86mm conrod length and 43mm stroke, the piston should be 2.4mm BTDC at 24.5 degrees BTDC.

Annotation2020-03-22104238.jpg

So I didn't really learn anything except the "Set the firing mark at 2.5mm BTDC" is damn good advice. - no surprise there..

Now to set timing without timing marks..

I now have my power drill set in low RPM mode with a fresh high capacity battery so hopefully the increased torque will more accurately hold it's max RPM (600). I've now marked the 600 RPM firing mark on the case. Next step is to find out where the crank shaft should be at 600 RPM.

I expanded my graph to show better what's going on from 0-1000 RPM. It looks like 600 RPM is dead on 17.5 deg BTDC

Annotation2020-03-22105126.jpg

After some lunch, I'm gunna hold the rotor at it's 600 RPM firing mark and rotate the crank until it's at 17.5 degrees BTDC. That should get me timed exactly on the money. I'll then make a baseline timing mark on the rotor with the tool I made yesterday. I'll just make some index marks from there +/- and I think I'll be able to make adjustments without even removing the motor from the frame.

Sorry if this shiz is drawn out and boring, but it helps with my thought process to type it all out

This single post is part of a larger thread. Start from the top or view this post in context.
Subject Written By Posted
  Vespa + HPI Mini RotorTopic by: Max (ツ) Max (ツ) 05/11/16 09:36PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/11/16 10:28PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 05/11/16 11:00PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/12/16 07:09AM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 05/12/16 09:55AM
  Re: Vespa + HPI Mini RotorRe: Mike Boyd Mike Boyd 05/11/16 11:19PM
  Re: Vespa + HPI Mini RotorRe: ***VANILLA BLUNDER*** ***VANILLA BLUNDER*** 05/12/16 09:18AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/12/16 11:22AM
  Re: Vespa + HPI Mini RotorRe: Dave Steele Dave Steele 05/12/16 03:43PM
  Re: Vespa + HPI Mini RotorRe: «tyler » «tyler » 05/12/16 09:09PM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 05/13/16 12:22PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/13/16 05:41PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 05/18/16 09:58AM
  Re: Vespa + HPI Mini RotorRe: MTech -> MTech -> 05/12/16 09:32PM
  Re: Vespa + HPI Mini RotorRe: «tyler » «tyler » 05/12/16 09:51PM
  Re: Vespa + HPI Mini RotorRe: MTech -> MTech -> 06/01/16 12:51PM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 07:19AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 09/30/18 02:51PM
  Re: Vespa + HPI Mini RotorRe: Dirty30 Dillon Dirty30 Dillon 10/02/18 10:50AM
  Re: Vespa + HPI Mini RotorRe: JBOT Admin JBOT Admin 06/01/16 01:04PM
  Re: Vespa + HPI Mini RotorRe: JBOT Admin JBOT Admin 06/01/16 01:16PM
  Re: Vespa + HPI Mini RotorRe: MTech -> MTech -> 07/25/16 08:10AM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 08:32AM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 08:35AM
  Re: Vespa + HPI Mini RotorRe: maxim vdb maxim vdb 07/25/16 10:23AM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 09/10/16 10:25AM
  Re: Vespa + HPI Mini RotorRe: Grande Guru Grande Guru 09/23/16 08:26PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 10/01/18 11:30PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/02/18 12:03AM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 10/03/18 10:20AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/03/18 11:32AM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 12:58PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/08/18 01:19PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 02:31PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 02:44PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 02:57PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 10/08/18 03:08PM
  Re: Vespa + HPI Mini RotorRe: scrot rash scrot rash 10/08/18 03:45PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/31/19 05:49PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 03/31/19 07:18PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/03/19 10:26PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/03/19 10:28PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/03/19 10:31PM
  Re: Vespa + HPI Mini RotorRe: Marc Friedman Marc Friedman 04/03/19 10:43PM
  Re: Vespa + HPI Mini RotorRe: Dave Steele Dave Steele 04/04/19 11:30AM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 04/04/19 11:37AM
  Re: Vespa + HPI Mini RotorRe: EH FCC of the QCB EH FCC of the QCB 04/04/19 06:27AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/04/19 07:26AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 04/04/19 01:58PM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 04/04/19 03:41PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/21/20 08:35AM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/22/20 12:02PM
  Re: Vespa + HPI Mini RotorRe: Max (ツ) Max (ツ) 03/22/20 06:43PM
  Re: Vespa + HPI Mini RotorRe: ᴛᴇʀʀʏ ᴅᴇᴀɴ ᴛᴇʀʀʏ ᴅᴇᴀɴ 03/22/20 11:01PM
  Re: Vespa + HPI Mini RotorRe: - Joe - - Joe - 04/01/20 08:40AM
  Re: Vespa + HPI Mini RotorRe: Graham Motzing Graham Motzing 04/01/20 09:05AM
  Re: Vespa + HPI Mini RotorRe: - Joe - - Joe - 04/01/20 11:53AM
  Re: Vespa + HPI Mini RotorRe: Daniel '' Daniel '' 04/01/20 09:51PM
  Re: Vespa + HPI Mini RotorRe: - Joe - - Joe - 04/02/20 09:34AM

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