Adjustable Steering Head Angle?
Discussion
I've got adjustable yokes on my R1. You will find that if you steepen the head angle (i.e. make the front forks more upright), you will feel the bike try and 'fall over' easier. When you first turn into a corner, it will seem like the bike wants to just tip into the corner. You may notice a slight decrease in straight line stability if you hit bumps, or if you're using the bike on the road, drive over cats eyes etc. You may want to consider fitting a s/damper to quell the effects of this.
If you're using the bike on a track, it will probably now hold a tighter line and allow you to turn in later without trying to run wide, etc. If you're using either slicks on the front or a steeply profiled tyre like a 207GP, the bike will now try and fall on its side. Get ready with the gas. You'll probably find you are needing to get on the gas earlier to steady the bike - which is no bad thing!
Just be aware that overall stability will be reduced. You may also need more steering effort at lower speeds.
You'll get used to it in no time mate!
PS this assumes you don't mess with the rear shock settings to alter the preload - hence sag, or the rear ride height, etc... You can cancel out some of the effects of the steeper head angle by dropping the rear of the bike to readjust the effective head angle. I'd speak to people like www.HMRACING.CO.UK or pete or Andy at Kais (google it), or Justin at Winning Performance suspension. I've heard very mixed things (both good and bad) about James Wilson at Setup in Wandsworth, London.... It's up to you. The best advice would be to change one thing at a time to guage the effect though.
To remove your front wheel, you'll need the following: a front paddock stand, a spanner to undo the bolts holding the calipers to their mounting brackets and a large socket/allen key to undo the wheel spindle.
Before the bike leaves the ground, loosen, but don't remove the front wheel spindle and also loosen the front calipers from their mounting brackets. Hoist the bike in the air, making sure it isn't going to fall off the stand! remove the calipers (LEAVE THEM ATTACHED TO THE HOSES THOUGH!) support the wheel with one arm whilst sliding out the wheel spindle with the other. You should now have a loose wheel in one hand. Lovely.
>> Edited by fergus on Wednesday 18th February 09:53
If you're using the bike on a track, it will probably now hold a tighter line and allow you to turn in later without trying to run wide, etc. If you're using either slicks on the front or a steeply profiled tyre like a 207GP, the bike will now try and fall on its side. Get ready with the gas. You'll probably find you are needing to get on the gas earlier to steady the bike - which is no bad thing!
Just be aware that overall stability will be reduced. You may also need more steering effort at lower speeds.
You'll get used to it in no time mate!
PS this assumes you don't mess with the rear shock settings to alter the preload - hence sag, or the rear ride height, etc... You can cancel out some of the effects of the steeper head angle by dropping the rear of the bike to readjust the effective head angle. I'd speak to people like www.HMRACING.CO.UK or pete or Andy at Kais (google it), or Justin at Winning Performance suspension. I've heard very mixed things (both good and bad) about James Wilson at Setup in Wandsworth, London.... It's up to you. The best advice would be to change one thing at a time to guage the effect though.
To remove your front wheel, you'll need the following: a front paddock stand, a spanner to undo the bolts holding the calipers to their mounting brackets and a large socket/allen key to undo the wheel spindle.
Before the bike leaves the ground, loosen, but don't remove the front wheel spindle and also loosen the front calipers from their mounting brackets. Hoist the bike in the air, making sure it isn't going to fall off the stand! remove the calipers (LEAVE THEM ATTACHED TO THE HOSES THOUGH!) support the wheel with one arm whilst sliding out the wheel spindle with the other. You should now have a loose wheel in one hand. Lovely.
>> Edited by fergus on Wednesday 18th February 09:53
fergus said:
I've got adjustable yokes on my R1....
I imagined it would speed things up, just not sure by how much. The bike is very stable as is, and although steering is slow by comparison to other bikes, it feels ok (I've got used to it) but I will probably try it on the steeper setting as I don't think it's a big job and if I don't like it can easily put it back to standard, only downside (according to manual) is that steering lock won't work on the steeper setting.
Think I'll try it on a good sunny day so as to best appreciate the difference.
veetwin said:
Oh yeah and how do you remove the front wheel as I need it balanced?
fergus said:
To remove your front wheel, you'll need the following: a front paddock stand, a spanner to undo the bolts holding the calipers to their mounting brackets and a large socket/allen key to undo the wheel spindle.
Before the bike leaves the ground, loosen, but don't remove the front wheel spindle and also loosen the front calipers from their mounting brackets. Hoist the bike in the air, making sure it isn't going to fall off the stand! remove the calipers (LEAVE THEM ATTACHED TO THE HOSES THOUGH!) support the wheel with one arm whilst sliding out the wheel spindle with the other. You should now have a loose wheel in one hand. Lovely.
Wheel removal as Fergus said above plus:
Having just replaced front tyre last weekend I can elaborate for 916/748, You'll need front & rear paddock stands, BTW the front wheel nut will need a 25mm socket (many socket sets don't have this size!)undo the 4 pinch bolts and shaft will slide out, although mine required an 'engineering' approach (big hammer
). you will need to remove the brake callipers before removing the wheel, they're a tight squeeze to slip off the discs.
Things to watch out for: when reassembling you need the alignment tool to ensure the wheel 'tube' is aligned correctly (otherwise you can't adjust the forks!) and make sure the speedo drive is correctly positioned i.e. the lug on the drive against the lug on the fork. Torque everything up to correct settings and there you go (Torque settings are in manual)
Behave!! Knowing how bloody badly made these Dukes are, I thought that I would make sure that I wasnt going to miss anything peculiar by removing the front wheel. The brake judder is still apparent at the front, and becoming increasingly worse. It nearly shook the front end loose two weeks ago flying down the dual carriageway towards J11 M25 from Ottershaw. I have checked the whole of the front end and the only thing untoward is a dent?!? in the tyre (not a flat spot). I am taking it down to road wheel this Saturday to get the tyre refitted on the rim and rebalanced.
BTW, AJ., The study is looking good now with the new Swedish computer desk and track day piccies decorating the walls. (God knows how she let those up!!)
BTW, AJ., The study is looking good now with the new Swedish computer desk and track day piccies decorating the walls. (God knows how she let those up!!)
VT
Try:
-worn discs
-badly out of balance tyre
-tyre that was poorly manufactued -it does happen?
Don't want to scare you, but if you have chronic wobbles, this can get so violent that you can have pad 'knock back' and end up with no brakes - you end up having to pump the lever to get your brakes back. This isn't really a ducati thing - just
ed discs I think... Get the front in the air somehow. You can use a trolley jack carefully placed under the sump on a duke and then spin the front wheel. You need to hold a fixed straight edge perdendicular to the forks to check the run out on your discs. Ideally you need a dial guage. You could do with strapping this on (oh er) to the forks so it's rock solid (oh er x2) to let you see how cattle trucked the dics is...
PS let me know if it's not the disc...!
Try:
-worn discs
-badly out of balance tyre
-tyre that was poorly manufactued -it does happen?
Don't want to scare you, but if you have chronic wobbles, this can get so violent that you can have pad 'knock back' and end up with no brakes - you end up having to pump the lever to get your brakes back. This isn't really a ducati thing - just
ed discs I think... Get the front in the air somehow. You can use a trolley jack carefully placed under the sump on a duke and then spin the front wheel. You need to hold a fixed straight edge perdendicular to the forks to check the run out on your discs. Ideally you need a dial guage. You could do with strapping this on (oh er) to the forks so it's rock solid (oh er x2) to let you see how cattle trucked the dics is... PS let me know if it's not the disc...!
Fergus my old mate, I have had the front end in the air last Saturday on the direction of Baines Racing, Silverstone. I originally wanted to check the runout with a DTI on a mag base but was informed that this would be no good as they are floating discs and the float could accentuate any play. The checks that I made were: a visual inspection of the disc rotors upon spinning the front wheel while elevated, pad condition check, caliper check, tyre and rim check.
The discs are spot on original Brembos that have only covered 6k miles. They arent scored or anything and look good from all angles when the wheel is spun. Pads are Brembo and are about 30% worn. The rims look spot on (marchesini alloys - 5spoke); the only thing I could find is this dent in the tyre. I am not sure about the balance though, this will get checked this weekend.
Shall keep you up to date,
PS Sorry about hijacking the thread somewhat. I am sorry that I have nothing to offer on head angle, however I would love to know what tool you need to tighten the headstock bearings???
The discs are spot on original Brembos that have only covered 6k miles. They arent scored or anything and look good from all angles when the wheel is spun. Pads are Brembo and are about 30% worn. The rims look spot on (marchesini alloys - 5spoke); the only thing I could find is this dent in the tyre. I am not sure about the balance though, this will get checked this weekend.
Shall keep you up to date,
PS Sorry about hijacking the thread somewhat. I am sorry that I have nothing to offer on head angle, however I would love to know what tool you need to tighten the headstock bearings???
VT
Sorry, didn't realise you had floating discs. There are two things to try. 1) your buttons will tighten up over time. Try getting a complete new set (around 12 quid or so for the complete set. It may be that the disc has stopped floating properly. 2) You can remove the disc and lay this on a glass (or flat) surface and try and slide a feeler guage under the disc at various points. A better way of doing this is to use engineers 'blue' and cover the disc (lightly) with it and lay it on some paper on top of your flat surface. 3) if the 'dent' in your tyre has appeared since the wheel was initially balanced, I suggest a) you get a new tyre before that one fails, or b) if you don't want to shell out, but don't mind a front end blow out, get the exisitng tyre balanced. 4) you may have hit a pothole with your wheels (are the magnesium) and hence knocked the wheel itself out of balance.
There can only be a finite numbers of things to check...
re your head bearings. IIRC there are two 'locknuts' at the top of the headstock. You need to get a screwdriveer (or 'c' spanner) on these and tap them round until they are tighter. Ideally, you need the front in the air (again) or at least with no resistance (i.e. tyre not on ground). There should eb no play in the vertical axis, but you shouldn't have to manually force the bars from side to side (this would suggest the bearings are overtight). This type of bearing should need too much preload I believe.
Later.
Sorry, didn't realise you had floating discs. There are two things to try. 1) your buttons will tighten up over time. Try getting a complete new set (around 12 quid or so for the complete set. It may be that the disc has stopped floating properly. 2) You can remove the disc and lay this on a glass (or flat) surface and try and slide a feeler guage under the disc at various points. A better way of doing this is to use engineers 'blue' and cover the disc (lightly) with it and lay it on some paper on top of your flat surface. 3) if the 'dent' in your tyre has appeared since the wheel was initially balanced, I suggest a) you get a new tyre before that one fails, or b) if you don't want to shell out, but don't mind a front end blow out, get the exisitng tyre balanced. 4) you may have hit a pothole with your wheels (are the magnesium) and hence knocked the wheel itself out of balance.
There can only be a finite numbers of things to check...
re your head bearings. IIRC there are two 'locknuts' at the top of the headstock. You need to get a screwdriveer (or 'c' spanner) on these and tap them round until they are tighter. Ideally, you need the front in the air (again) or at least with no resistance (i.e. tyre not on ground). There should eb no play in the vertical axis, but you shouldn't have to manually force the bars from side to side (this would suggest the bearings are overtight). This type of bearing should need too much preload I believe.
Later.
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