SetUp - Race Reps versus Heavy Weight Bikes - ZRX1200

SetUp - Race Reps versus Heavy Weight Bikes - ZRX1200

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oldninjaron

Original Poster:

44 posts

104 months

Tuesday 29th September 2015
quotequote all
Another two hours of daylight taken advantage of today. First warm up run, with two gallons fuel added, with rebound(R) and compression(C) settings front(F)/shocks(S) 50%, followed by runs as below:

............. Front..................................,Shocks..............

(R)Out of 15...(C)Out of 18....(R)Out of 60.......(C)Out of 24.

(F)(R)..........(F)(C)...........(S)(R)..............(S)(C)
8................. 9 ................ 30.................... 12 Initial run, v bumpy,bouncy cornering.
6................. 9 ................ 22.................... 12 Much worse, v uncomfortable thru bars.
7................. 9................. 26.................... 12 A little better but perty poor.
12.................9................. 46.................... 12 Better but not great.
12.................7................. 46.................... 11 Definitely improved - last run of day.

Initial rebound experiments not good reversed plus changed direction, small gain, needed compression tweek to feel better. Front definitely pings back at some rate after braking will revisit perhaps increase damping midrange between 50% and 12 clicks out. Last run felt more balanced over long bumps, appeared to rise and fall closer together. More work to come. Looks like big changes but Ohlins have huge adjustments possible so have tried to scale small changes on front to match.

Edited by oldninjaron on Wednesday 30th September 07:23


Edited by oldninjaron on Wednesday 30th September 08:17


Edited by oldninjaron on Wednesday 30th September 17:01


Edited by oldninjaron on Wednesday 30th September 17:01


Edited by oldninjaron on Wednesday 30th September 17:02


Edited by oldninjaron on Wednesday 30th September 17:09


Edited by oldninjaron on Wednesday 30th September 21:14


Edited by oldninjaron on Friday 2nd October 07:09


Edited by oldninjaron on Friday 2nd October 07:09


Edited by oldninjaron on Friday 2nd October 07:10


Edited by oldninjaron on Friday 2nd October 07:11


Edited by oldninjaron on Sunday 4th October 21:53

oldninjaron

Original Poster:

44 posts

104 months

Wednesday 30th September 2015
quotequote all
Two hours again, warmed up with settings from yesterday, thankfully still promising.

............. Front..................................,Shocks..............

(R)Out of 15......(C)Out of 18.......(R)Out of 60..........(C)Out of 24.

(F)(R)...............(F)(C)...............(S)(R)................(S)(C)
12................... 7 ................ ....46.................... 11 Initial warm up run - still fine.
11................ ...7 ................ ....42.................... 11 Instantly uncomfortable - reversed.
12................ ...6 ................ ....46.................... 10 Any balance prior gone - bad.
12................... 7 ................ ....46.................... 10 Unstable.
12................... 7 ................ ....46.................... 11 Back to start.
11................... 7 ................ ....46.................... 11 Not as good as start, back to start

After yesterday felt optimistic, felt on the flat sharp bumps felt softer and longer bumps felt front and rear close to rising and falling together - still felt pretty soft. My main concern is the bumpy bend once you a hit a bump it sends the bike into some sort of oscillation almost wallowing - not sure whether it is side to side or even back and forward then settles. It looks like happy with front end quite fast and I have tried to slow down fork compression to see if I can get some control over bumps on corners.
Throughout this challenge I keep trying to get bike front and rear rising and falling at same rate but have rarely managed it in the garage, pressing hard just behind petrol cap - the only time it sort of happens when bouncing on front seat but doubt it is at centre of gravity.

Edited by oldninjaron on Wednesday 30th September 21:46


Edited by oldninjaron on Thursday 1st October 22:43


Edited by oldninjaron on Friday 2nd October 07:15

oldninjaron

Original Poster:

44 posts

104 months

Thursday 1st October 2015
quotequote all
Work got in the way today so only had one hour of daylight available.
Testing the theory that my front end instability on bouncy bends could be down to too much compression damping at the forks:

(F)(R)Of 15......(F)(C)Of 18.........(S)(R)Of 60.......(S)(C)Of 24

12................... 7 ................ ....46.................... 11 Start
12................... 14................ ....46.................... 18 Felt much improved on bends.
12................... 7 ................ ....46.................... 19 Could be slightly better, rear harsh.

Tomorrow fuel top up need to see if that has an effect but promising - went for large change (C) front and rear as limited time for runs - pleased with results so far, plenty adjustment to try between start and finish settings.

Edited by oldninjaron on Friday 2nd October 07:08


Edited by oldninjaron on Friday 2nd October 07:12


Edited by oldninjaron on Saturday 3rd October 09:03

oldninjaron

Original Poster:

44 posts

104 months

Saturday 3rd October 2015
quotequote all
After previous days successes needed to check not upset by filling up tank - needed 3 gallons this time out of 5, putting in some mileage and time here. Forks still relatively stable on bumpy corners, thankfully.

Checked rider sag on forks just out of interest - reduced to 51mm, since last measurement despite fuel up, got to be red herring. Check it again when I have a mo - without damping.

Last night as still a bit harsh at rear, reduced shock(S) compression(C) bit by bit, working on assumption if rear too slow hitting the bumps rather than absorbing them on compression?


(F)(R)Of 15......(F)(C)Of 18.........(S)(R)Of 60.......(S)(C)Of 24

12................... 14 ................ ....46....................19 Start
12................... 14................ ....46.................... 20 Upsetting stability
12................... 14 ................ ...46.................... 21 Worse.
12................... 14 ................ ....46....................19 Back to start.

Unless I am missing something here, I seemed to have reached limit of compression damping at rear unless I need to reduce front even more, as well to attempt to maintain stability but with 18 clicks available forks and 24 shocks, always going to be a suck it and see experiment. "Telltails" on forks and shocks indicate a good 40mm available forks, still not sure if internal stops fitted, 10mm above shock stop.

Hopefully later today going to decrease some rebound damping on rear as rear still feels harsh, not sure if rear is squatting causing front to ride higher, may have to reduce fork rebound damping also to maintain stability?
More ramblings from a fella who is prone to learn the hard way tomorrow all going well - keeping shiny side up and as much rubber on the deck as possible.

Edited by oldninjaron on Saturday 3rd October 23:23

oldninjaron

Original Poster:

44 posts

104 months

Saturday 3rd October 2015
quotequote all
(F)(R)Of 15......(F)(C)Of 18.........(S)(R)Of 60.......(S)(C)Of 24

12................... 14 ................ ....46....................19---Start
12................... 14................. ....50....................19---Feels riding higher at rear, not too ......................................................................-------bouncy, might be something in this?
11................... 14 ................ ....50.................... 21--Interesting, flighty at front, too .......................................................................------much rebound?
12................... 14 ................ ....49....................19---Unstable?
12....................14......................48....................19---Worse, bouncy cornering
12................... 14................ .....50....................19---Try first change again.



Edited by oldninjaron on Sunday 4th October 08:43

oldninjaron

Original Poster:

44 posts

104 months

Sunday 4th October 2015
quotequote all
What a strange challenge this has been, things have not necessarily turned out quite as expected - perhaps a lot of preconceptions or misconceptions. I am not saying that bike is perfect but its not bad at all. Made a few adjustments today before the weather broke.

............. Front..................................,Shocks..............

(R)Out of 15...(C)Out of 18....(R)Out of 60.......(C)Out of 24.

(F)(R)..........(F)(C)...........(S)(R)...................(S)(C)
12................14 ................ 46.................... 19 Initial run.
12................14 ................ 50.................... 19 An improvement.
12................14................. 51.................... 19 It gets better.
13................14................. 51.................... 19
It could be some time before next run but need to run with this for now. If settle on this I will be amazed at just how little damping required?

Edited by oldninjaron on Monday 19th October 07:16

oldninjaron

Original Poster:

44 posts

104 months

Thursday 8th October 2015
quotequote all
Had a quick run out today before the heavens opened - turns like an ocean liner - perhaps too little rebound damping at front? Need to increase by one click at front.

oldninjaron

Original Poster:

44 posts

104 months

Thursday 22nd October 2015
quotequote all
Before adjusting forks rebound, given that front end really plush on test route, used Ohlins shock height adjust option at rear - equates to approx 10mm increase of shock length. Only had time for one run did seem to affect turn a little but would need some more time to test.
Got home, wiped off the bugs, but while oiling chain noticed rear tyre in a bit of a mess, looks completely goosed down the centre on a patch approx 1/4 of circumference and about half the width. Tyre has small cracks across the tread perpendicular to wheel travel!!!!

Current tyre Metzeler Roadtec Z8 190/50 ZR17, inherited from previous owner on a 6in wheel - standard normally 5.5. I have a 190/55 ZR17 of same make and model - I have know idea why he fitted 190/50 rather than 190/55 because standard on 5.5 wheel is 180/55. I am sure this will affect how bike handles anyway just based on its shape and height.

One thing I did notice, although predictable for some time, is how bike handles round slow bends over bumps, feels like front is bouncing side to side - I could be wrong but particularly noticeable round right handers - equal settings left and right forks, fork brace fitted, equal standard heights fitted in triple trees - now that does bug me????

Hooli

32,278 posts

200 months

Thursday 22nd October 2015
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Steering bearings?

oldninjaron

Original Poster:

44 posts

104 months

Friday 23rd October 2015
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Certainly possible, also possible mismatch between forks - oil heights, quality who knows? Thinking of getting Maxton modded forks serviced by them just in case. So far no answer from them re quote for this.

jason61c

5,978 posts

174 months

Friday 23rd October 2015
quotequote all
What spec is your zrx? It'd be great to see. I'm trying to build one, 25kg less than standard and 50bhp more.

oldninjaron

Original Poster:

44 posts

104 months

Friday 23rd October 2015
quotequote all
50 BHP more - now that would be heavily modded engine.

My Spec:

ZZR1200: Cams, valve springs, pistons and barrels.

ZZR1100D: Igniter, carbs and six speed gear box.

Skimmed head, lightened balanced crank.

Akropovic headers connected to twin, GSXR1000, Arrows cans.

Maxton modded forks, Ohlins shocks.

6 in rear wheel - ZX7R sourced.

Nissin 4 pots front.

ZX9R front mudguard.

Apparently 147 BHP at rear wheel - but this was according to previous owner - he has a newer ZRX12 with very similiar spec. All the mods make it as useful low down as a ZZR12/11 but eyeball vibrating stomp in theory, IMHO, all the way up to approx 11500 revs and thats without RAM air. It has immense torque so cracking top gear roll on and people wonder why I need it to handle. She is still pretty heavy though.

jason61c

5,978 posts

174 months

Friday 23rd October 2015
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This is mine. Currently making the chassis keep up with the engine.









Yoshi cams, flat slides, exhaust, 1253 big bore, mild head work.

I've changed the exhaust to thicken up the mid range even more. Once the chassis is done i'll fit a 6 speed box, lighten and balance the crank, and have the head properly sorted as its only ported on the inlet.

Just over 100lb/ft at the wheel does negate the need for 6 gears though smile

oldninjaron

Original Poster:

44 posts

104 months

Friday 23rd October 2015
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Sounds potentially awesome and extreme when finished - love the wheels and front end. Makes mine look pretty bland




oldninjaron

Original Poster:

44 posts

104 months

Friday 23rd October 2015
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Few changes since then - ZZR11C clocks different bodywork.

jason61c

5,978 posts

174 months

Friday 23rd October 2015
quotequote all
oldninjaron said:
Sounds potentially awesome and extreme when finished - love the wheels and front end. Makes mine look pretty bland

That looks like great fun. There's so much you can do with these bikes, part of the fun is that no two have to be the same smile

oldninjaron

Original Poster:

44 posts

104 months

Thursday 25th February 2016
quotequote all
Forks totally refurbished now - some wear plus air gaps mismatch.

Weather needs to improve before this soft geezer takes bike out for runs.





Edited by oldninjaron on Thursday 25th February 14:10

Prof Prolapse

16,160 posts

190 months

Thursday 25th February 2016
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Not being wide, but why bother?

Why not just buy a sports bike?




curlie467

7,650 posts

201 months

Thursday 25th February 2016
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Prof Prolapse said:
Not being wide, but why bother?

Why not just buy a sports bike?
If you don't get it then you won't understand, I don't really go for modern sports bikes but would love something like that.

Each to their own and all that malarkey.

Prof Prolapse

16,160 posts

190 months

Thursday 25th February 2016
quotequote all
curlie467 said:
If you don't get it then you won't understand, I don't really go for modern sports bikes but would love something like that.

Each to their own and all that malarkey.
Isn't that what Einstein said about Quantum theory?

I'm just wondering what the attraction is, I'm not quite sure the answer is that complicated.