RB250 SCOOTER SHOOTOUT MOTOR

Post your Lambretta dyno graphs here! But graphs & spec info only, keep the chat in the 'dyno chat' section ;o)
Steve Mac
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Wed Nov 14, 2012 5:57 pm

The wizard strikes again it must now be in the 100 mph + band

Darrell don't do Dave Rodgers RB the same he will never handle it (lol)

Steve Mac

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drunkmunkey6969
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Wed Nov 14, 2012 6:26 pm

Darrell Taylor wrote: ......he found the chain stretched and in need of adjustment and thought he would try it with a close ratio box.......
What box was in, and which one did you switch to?

Do you forsee problems with the power stripping teeth etc?
Darrell Taylor wrote:he found the clutch had started to slip so fitted new plates and heavier springs along with some new gearbox bearings that showed some wear.....
We run 7 plate clutches with MB springs in our high-power motors, what are you running?

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drunkmunkey6969
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Wed Nov 14, 2012 6:27 pm

Darrell Taylor wrote:std case with no welding to crankcases was matched to cylinder
machined for stroke/rod clearance
rb225 kit bored to 72mm (not advised skirt is too thin)
long rod 116mm
38mm keihin carb
lth or std inlet
franspeed race
varitronic or electrex ignition
std rb reed block
std rb piston with skirt/cutout mods
ron moss blank head and cowling i cut to my own spec cr/squish design

cylinder porting started with welding up the triple ex port back to a single port and welding up the 2 boost transfer ports to a single small boost port leaving it a very simple 1 exhaust port 5 transfer port design
i did resist welding the boyessen feeds up as development is approaching bmep figures that will start to need them soon and prefer to do it as a seperate test with a couple of balls of filler stuffed in either side ,i think people thought it was a wind up when i said weld up all the ports on the rb in a previous post,seen as a backward development step but u can see now i was serious.

the durations/widths/angles are to my own tuning specs and as the motor is also used in sprint events and the results are from months of hard development work and testing and weeks of lost wages and my personal time and money spent on testing various parts as well as eric the scooters owner time/money and effort spent
so im sure youll understand these elements of my trade will remain private
Thanks for adding this spec sheet in. And with the power you are producing, im sure you'll get a heap more questions!! l

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drunkmunkey6969
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Wed Nov 14, 2012 6:30 pm

Darrell Taylor wrote:cylinder porting started with welding up the triple ex port back to a single port and welding up the 2 boost transfer ports to a single small boost port leaving it a very simple 1 exhaust port 5 transfer port design....
Did you re-angle the boost port also? Made it a bit steeper maybe?

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drunkmunkey6969
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Wed Nov 14, 2012 6:31 pm

tonydevon wrote: nice to see an engine tuner thats happy to explain and put the time into helping others, obviously not the "trade secrets" but thats to be expected, they are your earners

too many forums and various other "hobbies" etc, the specialists are just silent and act as if they are some sort of gods
Totally agree, very pleased about this thread.....hopefully it will be a 'hot topic' for a while!

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drunkmunkey6969
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Wed Nov 14, 2012 6:35 pm

Darrell Taylor wrote:just checked for you and uncorrected is 48.13 bhp
s**t-a-brick.....48bhp! Thats got to be some kind of record for Lambretta tuning? Is there ANYONE else out there getting a higher figure?

We are building 2 Race/Sprint motors right now, one is TS1 225 and one is RB250......you have certainly set the bar VERY high Darrell. I hope we can produce something stunning for our customers too! ;)

Darrell Taylor
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Wed Nov 14, 2012 7:23 pm

Adam_Winstone wrote:Side float?

yes side float
feel free to use this link to contact me on facebook and like it(if u like it)
https://www.facebook.com/pages/Taylor-T ... 8819767924

Darrell Taylor
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Wed Nov 14, 2012 7:27 pm

drunkmunkey6969 wrote:Phenominal result.....would you hazard a guess that it is now peaking somewhere around 9500rpm??
no i think its still 8800 ,i put the rpm pick up on and got some half rpm/full rpm readings from it today
ill refit the electrex tomorrow and see for sure along with torque
feel free to use this link to contact me on facebook and like it(if u like it)
https://www.facebook.com/pages/Taylor-T ... 8819767924

Darrell Taylor
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Wed Nov 14, 2012 7:30 pm

drunkmunkey6969 wrote:
Darrell Taylor wrote: ......he found the chain stretched and in need of adjustment and thought he would try it with a close ratio box.......
What box was in, and which one did you switch to?

Do you forsee problems with the power stripping teeth etc?
Darrell Taylor wrote:he found the clutch had started to slip so fitted new plates and heavier springs along with some new gearbox bearings that showed some wear.....
We run 7 plate clutches with MB springs in our high-power motors, what are you running?
was li150 treated and now af cr ,time will tell i suppose
its the lth clutch which did hold on std springs but like you detected on your test ride started to slip a bit when cold,put some stronger springs in now but a bit too heavy at the lever so need to go somewhere between ,but its holding out
feel free to use this link to contact me on facebook and like it(if u like it)
https://www.facebook.com/pages/Taylor-T ... 8819767924

Darrell Taylor
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Wed Nov 14, 2012 7:31 pm

drunkmunkey6969 wrote:
Darrell Taylor wrote:cylinder porting started with welding up the triple ex port back to a single port and welding up the 2 boost transfer ports to a single small boost port leaving it a very simple 1 exhaust port 5 transfer port design....
Did you re-angle the boost port also? Made it a bit steeper maybe?
it was just a little less than std
feel free to use this link to contact me on facebook and like it(if u like it)
https://www.facebook.com/pages/Taylor-T ... 8819767924

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