Pulsating front brake/on off throttle

Squeaky back brake? Hard to control at 30mph/40kph?
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Rakamora
125cc
125cc
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Country: Swe
City: Uppsala
Year: 2013
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Pulsating front brake/on off throttle

Post by Rakamora » Wed Nov 28, 2018 9:42 pm

Hello first of all love the bike! Had it for 2 years very happy with it. I have a weird pulsating sensation in the front brake when speed is comming down. No vibrations at higher speeds this is most pronounced around 30 kmh - 0 kmh.

Even though i keep same brake pressure the breaking force is alternating when the disc turns(at slower speeds)

And is there anything i can do about the twitchy throttle? Very hard to transition from engine breaking to on power without the bike lunging forward in an uncontrolled manner.

And last question, is there a big service guide(with pictures) for beginners? Like fixing the oiljet and checking valve clearance?

Thx in advance.
Ride safe!

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Winterwolf
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Re: Pulsating front brake/on off throttle

Post by Winterwolf » Thu Nov 29, 2018 12:38 pm

Your disks could be warped?.. Or try cleaning up the disk bobbins as there supposed to be floating disks and need looked after?

Twitchy throttle is a common problem on then all.. And people normally get them remapped to try and help smooth them out

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limeyduffa
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Re: Pulsating front brake/on off throttle

Post by limeyduffa » Thu Nov 29, 2018 12:53 pm

Hi Rakamora

I first would be checking for seized front brake caliper pistons. What's the pad wear like ?

Fitting a straight thru can and remapping makes a big difference. Removing the emission features and following Kevxtx's mod #10 or mod #20 configurations makes the bike run how it's supposed to. Pretty much turns the bike into a good old fashion carb engine. No holes in rev range, no dithering throttle response.

Big service guide:

viewtopic.php?f=13&t=4946

The manuals are an under the table jobbie :)

J

Nordic09
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Re: Pulsating front brake/on off throttle

Post by Nordic09 » Mon Dec 03, 2018 9:51 pm

Situation is better if not vibration at high speed as I had. Anyway in my case I did use 6mm bolt and washers and nut and rust off to rotate singularly all bobbins through. Then I found couple of oval bobbins and was out of luck. Actually discs were more worn out on the middle and oval bobbins made it impossible to get disc radially center anymore. Due to worn groove there was vibration at high speed and really also felt oval at lower speeds. Cure: MRP discs from ebay, high cost but brakes are new and so good then.

Now I have also Ducati multistrada S with same discs, but it vibrated different way. Some high speed braking was helping, a lot, and in this case I believe that bobbins are only partly stuck, and will spray some rost off on the spring.

On off throttle, buy lonelec cable and put one of Kev’s maps in, 30 €s, and problem solved. Don’t try up-load during hangover, and consider instructions well, and it is easy. Well had some problem with driver and win10.
KTM SMT 2010 (Rottweiler and map in, secondaries, SAS and O2 off)
Ducati Multistrada S 2011
ex Triumph Street Triple R 2013 (too little torque)
ex Triumph Street Triple R 2011 (stolen)
ex Honda CR125 1989
ex Suzuki RG125 1985
ex Yamaha YZ80 1987

Rakamora
125cc
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Posts: 14
Joined: Mon Apr 24, 2017 8:26 am
Country: Swe
City: Uppsala
Year: 2013
Model: SMT

Re: Pulsating front brake/on off throttle

Post by Rakamora » Fri Dec 14, 2018 9:12 am

Thanks for all the tips guys!

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