Post by Justin(o) on Feb 18, 2011 21:24:22 GMT -8
Doha, Qatar 2/17/2011
Team TSI BMW S1000RR
Rider Nasser Al Malki
Yes, we are back for the next QMMF round, hoping to improve in both lap times and overall finished of a 1st and 3rd in the double header weekend! The last visit was a whirlwind of bad weather, minimal time for suspension tuning time (50 minutes) and significant tire tearing issues to fix. This time in arriving a day early, I had time to do some servcing work and take a much closer overall look at the race bike.
Chassis review:
Front forks:
The forks had over 120 laps on them at high speed with no oil change. I noticed a great deal of stiction in overall movement on the last trip so I decided to strip them down for a thorough cleaning. The obvious and immediate observations were
- there was almost no grease in the forks seals, and this was the root cause of the stiction.
- fork seals were cleaned and regreased
- fork oil was very discolored and when the last of the fork oil was removed, there were slight trails of metal debris in the oil from use
- the fork oil was replaced with and the fork oil level reset at a slightly elevated level to provide a slightly smaller air gap to assist with initial dive and too muxch weight transfer
- the fork height was changed to increase trail as stock triple clamps are in place, in raising them by 2mm.
The net changes are an attempt to make the fork ride higher in the stroke and to deceleate the compression stroke slightly giving more stability on trail braking into mid corner.
Front brakes:
The brake fluid was changed over a month previously and since that time Nasser had put over 100 laps on the bike at Losail. The brake fluid was overdue for a change and there were some late race fade problems encountered that validated the brake fluid change. The brakes were bled several times and that improved lever feel in regards to the lever pull distance shortening and the pressure feel on the lever itself.
In removing the brake calipers, the left caliper showed pistons evenly spaced whereas the right caliper showed unevenly spaced pistons (right side pistons out further) once again creating uneven brake pressure on each rotor. Both calipers were meticulouly cleaned and reinstalled. The wheel was spun without the brakes pads gripping the rotor to check for any slight bend in the left rotor, and no issues were found. The axle and pinch bolts were tightened correctly and the front wheel spun much more freely with the brake pads in place.
Close inspection of the ceramic pads saw significant fracturing and crumbling on the extremeities of the pad material. In an experiement to give Nasser more intial feel in trail braking, standard HH sintered brake pads were installed as Losail is not a very heavy braking track. The only consideration will be heat dispersal differences between the stock and ceramic pads which we will find out in the 30 minute qualifying session Friday afternoon.
Ergonomics:
There has been no real time to review this category thoroughly, so quite a lot of time was spent at the workshop in seeing how Nasser's body position was being compromised in an effort to make the bike do what he wanted to. This was behavior was observed in the last race evidenced by keeping the bike on the edge of the tire for longer than needed and in and awkward outside leg position on the tank. Hand controls and bar position were verified, but the peg location was to low. In changing the peg location, Nasser's outside knee fit perfectly into the tank when at lean and he even sat on the bike with the rear stand in place noticed a profound difference in fitting itno the bikie much more naturally.
Rear shock linkage:
This linkage had never been cleaned and greased, so it was stripped and reinstalled. Theer was not much grease on the bushings nor in the needle roller bearinmg area. Linkage action will be improved by this simple maintenance item.
The rest of the bike was gone through including chain adjustment and installation of new tires. The only task at the track is to set tire pressure and fill the tank with gas.
More to follow tomorrow!
DAY TWO AT LOSAIIL CIRCUIT, QATAR
The morning was again cold and windy but free of rain, and arrival time was scheduled for 8am at the track. Once there, we needed to get through registration and sign up, plus tech inspection during which the bike has to be weighed, and then rider gear review and inspection. Tire pressure was set and the tank filled with fuel and after that due to all the work done on Thursday at the dealership we sat around until 12.30 waiting to plug the tire warmers in for a 1.30pm free practice of 20minutes!
As the track opened, Nasser was reminded of and understood the nature of the changes made to the forks for new oil, seal grease and geometry and set off for the obligatory 2 warm up laps to then come in for a hot pressure check. By this time the track had warmed up considerably so rear tire pressure was set at 1.55bar. Nasser then worked specifcally on the following testing:-
With slight or no trail braking how does the bike turn compared to last race weekend where it was difficult?
Trail braking was improved with smoother fork descent, and the result was an easier turning bike on the brakes. With the ergonomic changes made, physically turning the bike was easier and Nasser was much more comfortable with his outside leg position. However, the taller fork setting and raised front end made the bike harder to turn off throttle even with the high compression and engine braking of the BMW motor.
The next session was 2 hours later so there was time to change the fork position by 3mm in lowering the front of the bike to evaluate if this change was too big to help off throttle turn in. Once Qualifying began (30 minutes), Nasser came in and made the rear hot pressure setting check which remained at 1.55bar even though the wind had picked up considerably.
He reported better turn in and much improved flickability of the bike, but the change created a very loose rear end when the clutch was released while braking and downshifting. Two turns of preload were added to raise the front end to slow down weight transfer during braking in an attempt to keep the rear tire more planted. We were unable to test further that session as the new Sato rear set sheared a bolt on the shift lever. We just had enough time to get Nasser back out to get in 3 laps to improve his qualifying time to 4th.He could have got very close to pole time but a sensor came out of aligment causing the traction control to interupt drive onto the front straight at the apex of the final turn just as the throttle was applied.
Final Ohlins R&T fork settings: fork height +15mm, preload 5 turns in, rebound 12 clicks out, compression 10 clicks out.
Final TTX shock settings: shock preload 6 turns in, rebound 11 clicks out, compression 9 clicks out.
Tomorrow is race day with a 20 minute warm up and then a double header of 15 laps races.
Team TSI BMW S1000RR
Rider Nasser Al Malki
Yes, we are back for the next QMMF round, hoping to improve in both lap times and overall finished of a 1st and 3rd in the double header weekend! The last visit was a whirlwind of bad weather, minimal time for suspension tuning time (50 minutes) and significant tire tearing issues to fix. This time in arriving a day early, I had time to do some servcing work and take a much closer overall look at the race bike.
Chassis review:
Front forks:
The forks had over 120 laps on them at high speed with no oil change. I noticed a great deal of stiction in overall movement on the last trip so I decided to strip them down for a thorough cleaning. The obvious and immediate observations were
- there was almost no grease in the forks seals, and this was the root cause of the stiction.
- fork seals were cleaned and regreased
- fork oil was very discolored and when the last of the fork oil was removed, there were slight trails of metal debris in the oil from use
- the fork oil was replaced with and the fork oil level reset at a slightly elevated level to provide a slightly smaller air gap to assist with initial dive and too muxch weight transfer
- the fork height was changed to increase trail as stock triple clamps are in place, in raising them by 2mm.
The net changes are an attempt to make the fork ride higher in the stroke and to deceleate the compression stroke slightly giving more stability on trail braking into mid corner.
Front brakes:
The brake fluid was changed over a month previously and since that time Nasser had put over 100 laps on the bike at Losail. The brake fluid was overdue for a change and there were some late race fade problems encountered that validated the brake fluid change. The brakes were bled several times and that improved lever feel in regards to the lever pull distance shortening and the pressure feel on the lever itself.
In removing the brake calipers, the left caliper showed pistons evenly spaced whereas the right caliper showed unevenly spaced pistons (right side pistons out further) once again creating uneven brake pressure on each rotor. Both calipers were meticulouly cleaned and reinstalled. The wheel was spun without the brakes pads gripping the rotor to check for any slight bend in the left rotor, and no issues were found. The axle and pinch bolts were tightened correctly and the front wheel spun much more freely with the brake pads in place.
Close inspection of the ceramic pads saw significant fracturing and crumbling on the extremeities of the pad material. In an experiement to give Nasser more intial feel in trail braking, standard HH sintered brake pads were installed as Losail is not a very heavy braking track. The only consideration will be heat dispersal differences between the stock and ceramic pads which we will find out in the 30 minute qualifying session Friday afternoon.
Ergonomics:
There has been no real time to review this category thoroughly, so quite a lot of time was spent at the workshop in seeing how Nasser's body position was being compromised in an effort to make the bike do what he wanted to. This was behavior was observed in the last race evidenced by keeping the bike on the edge of the tire for longer than needed and in and awkward outside leg position on the tank. Hand controls and bar position were verified, but the peg location was to low. In changing the peg location, Nasser's outside knee fit perfectly into the tank when at lean and he even sat on the bike with the rear stand in place noticed a profound difference in fitting itno the bikie much more naturally.
Rear shock linkage:
This linkage had never been cleaned and greased, so it was stripped and reinstalled. Theer was not much grease on the bushings nor in the needle roller bearinmg area. Linkage action will be improved by this simple maintenance item.
The rest of the bike was gone through including chain adjustment and installation of new tires. The only task at the track is to set tire pressure and fill the tank with gas.
More to follow tomorrow!
DAY TWO AT LOSAIIL CIRCUIT, QATAR
The morning was again cold and windy but free of rain, and arrival time was scheduled for 8am at the track. Once there, we needed to get through registration and sign up, plus tech inspection during which the bike has to be weighed, and then rider gear review and inspection. Tire pressure was set and the tank filled with fuel and after that due to all the work done on Thursday at the dealership we sat around until 12.30 waiting to plug the tire warmers in for a 1.30pm free practice of 20minutes!
As the track opened, Nasser was reminded of and understood the nature of the changes made to the forks for new oil, seal grease and geometry and set off for the obligatory 2 warm up laps to then come in for a hot pressure check. By this time the track had warmed up considerably so rear tire pressure was set at 1.55bar. Nasser then worked specifcally on the following testing:-
With slight or no trail braking how does the bike turn compared to last race weekend where it was difficult?
Trail braking was improved with smoother fork descent, and the result was an easier turning bike on the brakes. With the ergonomic changes made, physically turning the bike was easier and Nasser was much more comfortable with his outside leg position. However, the taller fork setting and raised front end made the bike harder to turn off throttle even with the high compression and engine braking of the BMW motor.
The next session was 2 hours later so there was time to change the fork position by 3mm in lowering the front of the bike to evaluate if this change was too big to help off throttle turn in. Once Qualifying began (30 minutes), Nasser came in and made the rear hot pressure setting check which remained at 1.55bar even though the wind had picked up considerably.
He reported better turn in and much improved flickability of the bike, but the change created a very loose rear end when the clutch was released while braking and downshifting. Two turns of preload were added to raise the front end to slow down weight transfer during braking in an attempt to keep the rear tire more planted. We were unable to test further that session as the new Sato rear set sheared a bolt on the shift lever. We just had enough time to get Nasser back out to get in 3 laps to improve his qualifying time to 4th.He could have got very close to pole time but a sensor came out of aligment causing the traction control to interupt drive onto the front straight at the apex of the final turn just as the throttle was applied.
Final Ohlins R&T fork settings: fork height +15mm, preload 5 turns in, rebound 12 clicks out, compression 10 clicks out.
Final TTX shock settings: shock preload 6 turns in, rebound 11 clicks out, compression 9 clicks out.
Tomorrow is race day with a 20 minute warm up and then a double header of 15 laps races.
