Monday 6 October 2014

Arai Corsair V Experiences and Review

I've decided to retire my Shark Speed R and upgrade to the Arai Corsair V. Here are some of the things that bugged me with the Speed R. The Speed R is very front heavy - due to the shape of the helmet - while doing head check's at speed it would feel like my head was being pulled to the side. Very annoying when changing lanes at any speed above 80km/h. The visor was a struggle to unlock when engaged in the fully locked position. And also - after 20 minutes of riding I was getting a headache around the back of my head behind my ears. If I pushed the helmet backwards the headache would go away but return soon after my hand was off it. I tried pushing the EPS foam in the area's of concern to relieve the pressure - it helped but was not a successful solution.

Enter the Corsair V - the shape is aerodynamic in all directions thus no head pulling at speed when head checking. The visor lock system is amazing. However the headache issue still existed. I am between sizes for the Corsair V - the S is a bit tight but the M is too loose. So I opted for the S hoping that it would stretch/expand/adapt over time. The headache around my ears was so acute after 15 minutes that I started to question my investment. I then tried the 5mm comfort liner available from Arai (standard is 7mm on a size S). What I discovered was that the 5mm liner is not only thinner around the circumference of the head but the top pad is also thinner. I didn't like that so I removed the top pad from the 7mm liner and swapped it over to the 5mm liner. With the 5mm top pad it felt like the helmet sat too low on my head - the 7mm/5mm Frankenstein liner I made up solved this. Upon testing - the headache still came - albeit slightly less severe. So I averted my attention to the cheek pads - the standard cheek pads have a 5mm fine tune pad that can be removed. I removed this piece and also did some shaving with a razor blade around the area that situates around the ears. This relieved the pressure and now I've not been getting headaches anymore. 

A comfortable and properly fitting helmet is absolutely imperative to the whole motorcycling experience. I just want to thank Arai for making a helmet so adaptable and fine tune friendly. Love it!

5mm/7mm comfort liner


Saturday 6 September 2014

10 Months ownership update



The little 250s has a touch over 3000km's on it now Being the pedantic guy I am I've done 3 oil/filter changes already. 

The following are some of my discoveries on the bike - 

Engine stalling while clutched in and downshifting. I have heard of many others experiencing this issue however there does not seem to be a fix. My theory is that when engine mapping is in a fuel-cut state when on the over-run (rear wheel driving the engine) - when the clutch is disengaged thus no drive is being transferred from the rear wheel to the engine - the engine can cut out on compression stroke due to lack of inertia - this phenomenon is further exaggerated on a single cylinder low inertia engine like in our 250R's. Now a possible fix would be to map the ecu so that the injector delivers a small amount of fuel when the engine is in the aforementioned state (clutch switch open, throttle closed, rpm mid-low). However it is not a big enough of an issue for me to bother going down that route as it only ever happens when I'm being lazy and not rev-match downshifting and even then it is a rare occurrence. 

Lack of front end stability while travelling over 120km/h. Hitting bumps mid corner really seems to unsettle the front end creating a squirming/shimmy. When riding over 150km/h the same occurs while just travelling straight - where the front end feels light and unstable. I am still under investigation on this to find a possible fix. I suspect it is due to a culmination of things: weight of bike, lack of steering damper, less than perfect damping performance of the forks, tyres. I'll report back on my findings as I play around with the settings. As now I have Racetech cartridge emulators, uprated springs and preload adjusters in the forks. 

Another issue the bike seems to have is a metallic rattle when accelerating (light-medium throttle). I suspect it to be the cush drive rubbers so I'll be opening them up and seeing whats up. 
(Update: lubricating the chain has removed the noise. Seems like lubing the chain is a very frequent requirement - like once per fill up rather than once every 2-3 fill ups which about was how often I did it. The cush drive rubbers were perfectly fine. I reinstalled them with a touch of silicone grease to decrease the wear/beading of the rubber.)

One more thing to note, when raising the pegs with aftermarket rearsets or brackets - the kickstand foot protrusion becomes the lowest part of the bike when leaned over, so that needs to be cut/bent/re-positioned/re-welded so that is doesn't hang so low. I nearly low-sided once when it scraped!

Monday 17 February 2014

CBR250R First Service - Valve Adjustment

So the CBR hit nearly 2,000km's before I got around to doing the first service. Been holding off due to the task being quite time consuming (around 2-3hrs if no shims need to be replaced) and I had already changed the oil at 500km's. 
Before I went for it I had a read of this walkthrough. The walkthrough is very detailed - awesome work by the editor. I do have to say though, its not an enjoyable task. The fuel tank is difficult to remove due to the tricky fuel hose connection and the rocker cover only *just* makes it out between the radiator and wiring harness so refitting the rocker cover gasket is fiddly. I didn't have a proper tool to remove the timing cover caps so I ended up using coins and they worked perfectly. However I did have to hit the caps with a hammer behind a rag to break up the bond before I could wind them out.
Both intake and exhaust valves were well within spec - no replacement of shims was necessary. That saved me a lot of time otherwise it'd be an easy 3-4hr job if shim change was required as the rocker arms need to be removed.
Back in one piece




Tuesday 21 January 2014

Woodcraft Clip-ons Installation & Review

These woodcraft clip-ons for the CBR250R claim to lower the bar height by 1.5" (measured at the end of the bar). However I found the main factor that is most influential to the ride is the angle these bars are compared to the standard clip-ons. The woodcraft bars angle downwards a lot more - which creates a cockpit style similar to other more focused sport bikes. 
Instructions are vague and universal - so here are some CBR250R specific pointers. 
The circlip on the fork uppers need to be removed! A small flat head screwdriver will do the trick. 
Removing the bar ends requires a lot of force and a pipe wrench or multigrips to hold the bar end from rotating while undoing the philips head bolt. Either that or use an impact screwdriver of sorts. Take care and use tape to protect the bar end when gripping it with the monkey tools.
Taking the clutch side grip off requires compressed air. This is the single best way to do it. The other methods are a struggle.
Throttle side grip comes off with the throttle assembly. Best way is to not disconnect any throttle cables, just loosen the standard clip on, remove the phlips head screws (two or three) - open up the throttle assembly and slide the standard clip on out while holding everything in place rather than pulling it away. This enables you to remove the assembly from the bars without having to dismantle the throttle system - the cables stay in place. 
4.5mm holes must be drilled into the each of the bars for the electrical/throttle assemblies. Refer to oem clip ons for hole location and just replicate it on the new bars. Make sure you dont drill the holes too big as this is the only thing that holds the controls from rotating on the bars. A hole too big means the locating pin will have too much freeplay thus you'll end up with very annoying and dangerous rotating switches and throttle!!! 
Conveniently - the machined edges on the crown of the fork somewhat matches up to the yoke of the woodcraft clip on in a way that locates the bars at an ideal angle - you'll notice this when you have the clip on clamps slightly loose and you rotate the bars around the fork uppers. Just meet these edges and torque up the clamp bolts. This is the correct bar mounting location as everything clears perfectly - no cable fouling, no fuel tank fouling at full turn, levers clear the windscreen.
Now - the main issue with aftermarket clip ons is vibration at high engine rpm.
The weighted shaft inside the standard bar can be removed - thread the philips head bolt back into the threads of the weighted shaft and use a flat head screw driver to pry the prongs inwards (towards the centre of the cross section of the shaft) while pulling on the philips head bolt. Alternatively - take the grips off first and then you'll see two holes at the end of the standard clip ons that locate the circlip that holds the weighted shaft in place. You'll need to push down on the circlip through these holes while pulling on the shaft to remove the assembly. If you are mechanically minded enough, you can make the oem anti-vibration weights fit the new bars. The main issue here is that the woodcraft bars are aluminium - thus thicker and the internal diameter (ID) is smaller than the oem bars. The weighted shafts fit in perfectly but you'll need to get creative with the circlip and use some different O-rings to get it to fit in the smaller ID of the new bars. I managed to get it to fit after a good hour or two of tinkering. And it makes a world of difference to the vibration at high rpm.
Before

After

(You'll notice in the after photo that I hadn't worked out the anti-vibration bar ends yet)

Riding Impression - God Awesome! Coupled with the Yoshi rearset brackets - the ride is transformed. It feels much more like a sport bike should and when cornering hard it doesn't feel like your hands are being held above your head so much. It is a very time consuming install but the result is well worth it. When the bars are mounted in its correct (aforementioned) location - there are no issues with fouling - everything clears - it is a tight fit but it works. No cable fouling at all. No fuel tank fouling at full lock. Woodcraft definitely are true to their words when they said this is the lowest you can go on a CBR250R.


Yoshimura Rearset Brackets CBR250R Installation & Review

The Yoshimura Rearset Brakets for CBR250R 11-13 pulls the pegs back 45mm and up 30/45mm depending on mounting location.
Box contents includes 4 hex head bolts/washers, the two brackets, and also an extended shift linkage rod.
Installation is pretty breezy for the mechanically minded.
On the Brake side - the rear brake reservoir hose (hose going from res to master cylinder) requires shortening and depending on where you set the height at (30 or 45mm) determines how much you'll need to cut the hose down but a ballpark will be around 15mm. With ABS models the plastic shield surrounding a brake hose junction block will also need to be removed so that the aforementioned hose clears/does not kink. Setting it at 45mm will probably require further manipulation of the brake hoses to ensure kink free operation. Non-ABS models should have a much easier fitment. Remember that after you set the brake pedal height that you make sure that the stop switch is adjusted right and not held on - thus holding your brake lights on with no brakes applied.
On the Gear side - fitment is very straight forward on this side - I went the extra mile and re-located the gear linkage counterclockwise one spline over to maximise thread overlap of the linkage rod into the ball joints. Remember that one of the M6 linkage rod locknuts is reverse thread so don't lose it as they are rare as hell.
I didn't have to file or grind down any metal which is good.
Riding impression - Can definitely feel the difference immediately. Took a decent ride to get used to the new riding position. Also took a few attempts to get the gear and brake levers adjusted right as with the new peg location the levers need to go further down to feel right. Once all adjusted the position felt a lot more aggressive and sport focused - pulling the peg location rearward and up naturally made my upper body hunch over the fuel tank more and knees angle increase. Please stay tuned for the woodcraft clip on review as I will go into more detail on this.

Akrapovic Slip on - CBR250R

First mod - CF Akrapovic slip on

Fitment - very simple - two bolts. However taking the old graphite exhaust gasket off (at the slip on junction between the standard pipe and the aftermarket slip-on) can be tricky. If you can manage to fit the slip on over the stock exhaust gasket then do so - otherwise, hammer and flat head screw driver chiseling away will do the trick. New gasket is tight to go on and can be difficult to get it all the way in without damaging it so you're definitely better off leaving it alone if you can.
Exhaust db level will be above legal limit even with the silencer in place. The rasp is aggressive with moderate volume level. It does make drivers a lot more aware that you're next to them which is a huge plus - the standard exhaust makes the bike hardly audible. 
Fitment of the carbon Akra (among with most other slip on systems) will result in boycotting the oem catalytic converter as it is located in the oem slip on. As a result theres a bit more fuel smell on cold starts. If you wish to keep a cat in place you can purchase the stainless steel Akra which can be adapted with Akra's catalytic converter. 
There seems to be the tiniest improvement in pick up at high rpm - hardly noticeable. 
You will notice some plastic burning smell as the exhaust wears in - after about 200/300km's it was gone.
Last but not least - the weight saving is tremendous! The stock slip-on with heat shield weighs around 7kg. Akra's system weighs around 2kgs.
Happy riding!

Day 1 - Brought the bike home

December 3rd - Took delivery of my new 2013 CBR250R ABS
The purpose of this blog is to share my thoughts and experiences as a CBR250R owner.