Posted on behalf of Bufficus, a really good write up of his own work!
TS1 from standardish spec to home tune 230.
The first graph shows a pretty standard TS1 with no porting.
MB piston 70mm
AF race crank
AF head
Mikuni TMX 30mm
ScootRS pipe
Indian static stator timed at 18 degrees
Matched casings
Yamaha reed block (standard yam reeds) and MB inlet
When I first had this dynoed by John at JB tuning I was a little underwhelmed. I was hoping for 20bhp, but it came in at just under 19.
John was surprised at my dissapointment and said 19 was pretty good for a standard barrel on his dyno. A couple of other standard TS1s made between 17 and 18 that day. Going by Sticky's dyno comparison article in scootering JB seems to have the lowest reading dyno around.
Changes had to be made. I decided to tune the barrel myself and change a few components.
60mm Alpha crank
MB head/AF head
Devtour pipe
Mikuni TMX 35/TMX30
exhaust timing 185 degrees
transfers 125 degrees
The motor was dynoed again by John ( sorry no graph) and this time put out 22.5 bhp @ 7125rpm. Torque 15.5ft/lb.
It was dynoed with both an AF head and an MB head, which made no difference and also with a TMX 35 and a TMX 30, again no real difference.
With this spec the moter was a joy to ride, but I decied to go a bit further.
Minor changes were made to the barrel
Exhaust timing was changed to 190 degrees
Transfers 133
JL4 pipe
V force reeds
Augusto box
Dellorto VHSB 34mm carb
The carb was changed because it was impossible to jet the TMX 35 cleanly at 1/4 throttle (unpleasantly rich) I was on the top clip of the leanest needle
and had nowhere else to go. However, I did try modifying a slide, but went too far
so at £35 a go I decided to stop with the Mikuni.
Now reading 25.3 BHP @ 8151rpm and 17Ft/lb torque.
Of course the power has moved up the rev range and is not as nice to ride for touring, but it is fun in the right conditions.
