Lennies Rocket Sprockets 9 degree cam timing advance for BMW R series twins

lennie

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Hi all,

I have been keeping a low profile as I have been busy with my other business.

I have a new machinist that has further improved the quality of the Rocket Sprockets which are our 9 degree advanced cam sprockets. We have made a change to the cam locating pin hole so that is in now a blind hole.

I have a new batch of 50 sets and they sell for $230.00 AUD, 125.00 GBP, 160 EUR or $202 USD including postage worldwide.

The sprockets lower the torque peak by 800 to 1,000 rpms and improve throttle response and ride ability for all models.

They fit all for all years from 1994 to 2009 and all R850, R1100, R1150 and R1200 models.

I hope all here have been well and having lots of fun riding.
__________________
Lennie

www.boxer-performance.com
 
I must say I am very pleased with the improvements to my 1150 after having fitted a pair of these. The difference is noticeable everywhere that I used my engine. Far fewer revs are necessary when starting off and the E gear is useable at much lowere speeds, too. More grunt. If there's any loss at the top end, I haven't missed it. So, cheers Lennie!
 
Hi Kaister,

Slotted sprockets are not possible and I have posted a photo of the back of the stock sprocket and the Rocket Sprocket.
 

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Why did BMW choose the cam timing they did and not what these sprockets give ? Genuine question as I have a pair but I'm undecided on fitting them .
 
Hi Andy,

Most manufacturers build engines to suit a particular application and the cam timing is decided upon to suit this application. What I have done with advancing the cam timing is a common automotive practice as part of dialling the cam into the engine for optimum performance. We advanced the cam timing 3 degrees at a time with vernier cam sprockets I had made and settled on the 9 degrees as it had the best result. This effectively lowers the torque curve 800 to 1,000 rpms depending on the particular BMW model.

Once you fit the sprockets you will not want to remove them as they will make the bike so much better to ride.

Let me know what you decide and how you go with the fitment.

BTW there is only one part for all models.
 
Hi Lennie ,
I understand what its doing but was just curious to why BMW went with what they did. Is the peak HP higher on the bmw sprocket , it just baffles me why BMW wouldn't have set the timing the same as yours in the first place. What was the application BMW were after ? If that makes sense.
 
Hi Lennie ,
I understand what its doing but was just curious to why BMW went with what they did. Is the peak HP higher on the bmw sprocket , it just baffles me why BMW wouldn't have set the timing the same as yours in the first place. What was the application BMW were after ? If that makes sense.

Because some muppet is at the controls in Casa BMW

They are always pushing for BHP these days as

The public demand BHP it is their human right to have it !!

Sad that they don't know "usually" to gain BHP you sacrifice torque

Check outputs of other manufacturers BHP figures just go up and up


Lenny I think When I get a few quid "Gertie" will be getting a pair of these
 
Just to add to the thread..

I've had a set of rocket sprockets fitted to mine quite recently, a great improvement!

It's like a new machine, loving it!

It's had some other items 'serviced' but the overall effect with these sprockets has made the bike easier to ride from lower revs...:thumb

Impressed, Cheers Lenni! :beerjug:
 
This seems like a good modification to smooth out the engine and give more low end grunt.
What comes to mind is an ECU download to achieve a similar result.
Does this mechanical mod differ from the electronic one re engine performance/torque/smoother pick up etc?
 
hi Brut,

the sprockets mechanically advance when the valves open and close and this is why the torque peak is lowered.

ECU tuning is good for fueling and spark timing chances to optimise the running of the engine and some form of chip tuning or after market device can help.

to all.

I now have access to a R1200ST that shares part numbers for the standard intake with the R1200RT and I will develop an InDuct for these models. I am looking for a R1200GS intake so I can make a plug for an InDuct.
 
Anyone done a before and after Dyno test to see what the figures say.
 
Nobby,

I had the before and after dyno sheets years ago but with system upgrades they have been lost.

Brad Black who helped get chips developed by FIM has many dyno sheets and reports on his site at www.bikeboy.org .
 


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