Been off Piste for a while

Need help from a fellow owner, something to air - discuss away!

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greenwoo
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Re: Been off Piste for a while

Postby greenwoo » Mon Jan 18, 2021 11:39 am

ohhh someone's been busy.

What does the bias info tell you Lee? x% front and y% rear?
what do you have that set to for a normal dry day?

i wondered about a net too, not just for safety but aesthetics ....still a bit undecided.
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leegav
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Re: Been off Piste for a while

Postby leegav » Mon Jan 18, 2021 2:18 pm

There were a few reasons why I decided to fit the brake sensors. 1 was to try and confirm if I actually had a problem with too little pressure at calipers, hence why car felt like it wouldn't stop. I wanted to be confident that everything was as it should be and two so I can see exactly what psi I'm running front and rear.

I tried to work it out using some maths and built quite a detailed XL spread sheet to show different conditions that would effect psi. Such as pedal ratio, MC sizes and caliper rod diameters.. But decided the best way to know for sure is brake sensors. It also helps diagnose any issues should there be any leaks. And so does the UV.

Now instantly what the sensors told me after I'd fitted them was the pressures were terribly low. Around 300 and 400 with a very hard push. and also that the bias bar at peddle end should have gone in the other side of the peddle because when i dialed pressures up at front they went down!! So...I jammed the peddle down with wood overnight to see if anything changed with pressures. In the morning pressures were down alot, but i was confident any air bubbles would have moved to the highest point so I bled the sensor and unions front and rear first... Got a big jump in pressure on the wheel. Then bled a caliper on the front but hardly got any fluid movement at front caliper, this again was down to too much dial in on the rear so the front push rod couldnt move enough to get full movement of the peddle to the firewal.

I found out it is vital if your running a brake bias and two separate MC that you bleed front and back right or left together so the master cylinders are pushing fluid through together and you can get full range of movement on the peddles. I also pumped the peddle a good few times in quick succession and managed to get a huge bubble out from somewhere at the front.
Now all closed up and pressure check again I could balance the bar with 5-10 psi of each other sat at almost 1000 psi at full stamp. that tole me my balance bar was about 60/40 because i have two different size master cylinders which push different psi at the same amount of foot pressure.

So essentially what I've done now is recreate how hard I will stand on the peddle whilst driving, so I did this for about 5 minutes then checked all bleep nipples and unions and sensors for leaks again and set the bias bar so i had on 60% front 40% rear PSI readings under a certain foot pressure.

With the pressures at 60/ 40 I can see just shy of 1200 psi front with a hard stomp. Less rather interestingly when you press the peddle controlled but hard. I think I am going to see how it feels on the road but may dial in some rear more, and that is because it's a bigger MC at the rear which means I get a firmer peddle the more I dial in rear...but got to balance that feel with pressures.

What I'm going to attempt to do is drive the car and if I still feel the peddle has too much travel despite being able to stop very well at around 900 psi front I'm going to change the front and rear master cylinders up one or two sizes to get a firmer peddle.

Now, the 24v start system is something all the sr3 r1500cc radicals are set up with. Due to the high compression engine when hot they can have trouble starting, something I have had trouble with when I have stalled at a T junction. Also the electric reverse takes a lot of juice out the battery so was difficult to start of car was hot and I'd just tried to reverse too.

All you need to do is remove the one wire from the starter solonied and add this to the negative side of the second battery, then add a new wire from positive side of second battery to starter. There is the risk of eventually burning out the starter but listening to advice it takes alot of turn overs to do this. You also need to charge the 2nd battery seperate to the first one every now and then.

https://www.demon-tweeks.com/uk/ring-uv-dyes-250947/

UV dye link
Say NO to Pheasants !!! Body count = 3
Say NO to Blackbirds !!! Body count = 1
Say NO to Marmots !!! Body count = 1
Say NO to Squirrels!!! Body count = 1


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