Scooterotica

Adspeed wrote:More graphs & specs please!!

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.

Good work Bifficus!! Just sat plotting over a couple of graphs as we speak - maybe I am getting obsessed!!

Great to see the results of your hard work rather than just saying 'its faster'!! And with detailed engine specs too great stuff!!

Now let me have a closer look......





Maybe a Sticky in both Lambretta and Vespa sections would be nice as theres lots of graphs going on at the mo ( )and they're really good to look back on from time to time? Sean?

thats a good idea Badspeed...

He aint Badspeed no more sean... he's Ad-min-speed!!

Hi Bifficus.
Is nice to see the progress in the Dyno changing things in your config.
Can you answer me some questions (newbie questions)?
When you play with exhaust and transfer degrees, you play with base gasket or you use a porting tool to do this job?
If you use a porting tool to open this exhaust and transfers, after this job you must rebore the barrel?
Thanks for your help!

Arkaitz

ArKaTxU wrote:Hi Bifficus.
Is nice to see the progress in the Dyno changing things in your config.
Can you answer me some questions (newbie questions)?
When you play with exhaust and transfer degrees, you play with base gasket or you use a porting tool to do this job?
If you use a porting tool to open this exhaust and transfers, after this job you must rebore the barrel?
Thanks for your help!

Arkaitz

The exhaust port has been raised slightly and widened quite a lot. I used a dremmel type tool to remove the material from the barrel. I did not have the barrel relined after the port work as my nicasil is in good condition. The Alpha crank I have fitted has a 110mm long rod, so I can adjust the port timings by usuing different thickness base packers and gaskets if necessary.

Hope this helps.

Great post, hoping to get down to johns in the new year for a tune on my RB..One question are you one of the 2 people who won the 45 million. I only ask as you seem to have gone through about £600 worth of pipes alone.... NOt envious you understand...

sydduckett wrote:Great post, hoping to get down to johns in the new year for a tune on my RB..One question are you one of the 2 people who won the 45 million. I only ask as you seem to have gone through about £600 worth of pipes alone.... NOt envious you understand...

No millionaire I'm afraid. I used to spend all my spare cash on my scooters, but I've calmed down a bit now since the baby came along and I'm now self employed. My trouble is I'm good a buying stuff, but not so good at parting with things I no longer use. I justify it to myself by saying it will give me options for the future. Luckily my Mrs doesn't know the price of anything and doesn't seem mind anyway.

G'raph I spotted recently...

Couple of weird spikes in the middle and two flat areas either side. Some room for improvement I think...
He's having a giraffe with that g'raph!