Well after taking my 250 to the track a few weeks ago I have decided to make the bike more track worthy. While riding I noticed the front brakes are kinda needing a bit more bite to them, I already have steel braided line, but the brakes are still lacking. Also the front shocks just drop out on hard turning, the bike did hold the line fairly well, but hit a bump in the track and she goes all over the place. The rear shock is okay if you weight 160 lbs, however I do now weigh that. So a new rear shock will have to go in place of the stock one. Myself and a friend who is a track safety inspector also a Kawi 250 rider have set down looked all over the internet and decided what we fill will be the best for the CBR to be more track worthy. I will share the links of what I have already purchased for my 250. I am 6'2" and tip the scales at 230 lbs. While my 250 will be getting an upgrade I have decided to get myself in a little better shape also, as the power from the 250 is also lacking so I will help it out by losing some weight.
15 tooth front sprocket will get locally. All parts that have been ordered were what will work for me as for price and shipping. I live in the Philippines so parts and availability could be cheaper for you in America. I will update the results once everything is here and installed on the bike. Total for parts and shipping came out to around $1200.00 the above mentioned guy that help me locate everything has done this to his Kawi 250 and the bike feels, rides, and handles amazing. I am sure I will get the same results for my 250 also. Thanks for looking through my thread.
Yes everything is still stock on the suspension.... The bike was going to be pure show bike, but I really liked it on the track, so now it will have a better life
I see you are upgrading the springs which will make a huge difference. You should look into the RaceTech gold valve emulators also if the class you are racing in allows them. They will let you have more control of the compression damping and then you can play with oil weight to get the rebound dialled in.
@Jme250RA Thanks for the info I will look into them. I am not sure if I will get into racing, maybe next year once the bike is all set up, but with my work schedule I will miss half of the races. You know of some cheap/decent fairings I can get? Would hate to mess up my paint job.
On another note the brake kit isnt available until Dec 3, 2014 so the stock brakes will have to hold for now. Maybe I will look into getting Galfer wave rotors for now. They will help out I am sure. Am so excited cant wait to get everything here and installed. Then the fun begins testing it out on the track
Remember, there are no dumb questions... only dumb people!
And the answer is, yes it is possible to lock the front wheel on dry pavement with or without track tires.
ability to lock up the wheels is not why people upgrade brakes. Almost any vehicle can lock up it's wheels once. My 1960 beetle w/ drums could lock up from 60mph pretty easily, but that doesn't mean the brakes are good.
You may need "better" brakes for 2 reason:
1) Feel. Locking up actually extends braking distance pretty significantly. On a bike, it also means you're pretty likely to fall over. Also, you lose all ability to steer. So, you need good feel so you know when you're about to lock up before it happens so you can back off and maintain balance and steering, AND so you can stop faster
2) Heat. Stopping once is relatively easy. Hitting the brakes hard, repeatedly heats them up. And if the system can't deal with the heat, you don't be stopping again. At least not upright. You'll stop when you hit that wall after your brakes give out.
When brakes are used almost constantly, on the track mostly, they don't get a chance to cool down and the heat soaks into the calipers and fluid. When this happens you get what is called brake fade. Because brakes work by turning the kinetic energy (forward motion) into heat, the cooler they stay, the better they work. As the heat builds, the brakes become less effective. To combat this, engineers design disks with vent holes in them and make calipers with more & smaller pistons so they cool faster.
Why a 15T sprocket?... seems like that would be going backwards in terms of acceleration for a track bike. I believe that Aufitt was running a 13T front sprocket on his CBR250R race bike.
Now that I think about it thats right @MotoMike I did a -1/+3 on my liter bike and it was faster acceleration, glad you caught that. I can get it locally so I will go 13t instead of 15t.
Sorry for not updating been having to pay for my own internet so I havent been posting much, have a lot to upload with many pix. After ordering the Front brake conversion kit from Webikejapan, I got an email they are out of stock will be restocked Dec 3rd, emailed them Dec 4th the reply they are no longer making and have stopped selling the conversion kit..... FAK ME!!!! Now with that news the mechanic says just get the sinter pads and squeeze the lever harder. Will try that for now, if needed be ill get a 16 X 18mm master cylinder later.
First the Bog bore kit. 305cc
Port and Polish
Test fit of bore kit
getting squishy, had to mill the cylinder down to get higher compression ratio
Racing cams installed
After motor work was completed and mechanic satisfied he moved on to the clutch. Plates and clutches were all within spec so no need to change them.
When clutch was buttoned up he moved on to the custom header pipe
Since the local dyno was down until February it was decided to get an Auto tuner to go along with the Power Commander V from Jett Tuning.... Insert bung here
While waiting on the rear shock from Ohlins he got to work on the front. Didn't get any pics of disassemble or reassembly. Looks like a BIG BIKE now
After 1 month the rear shock finally made it took longer as they had to order the stiffer spring from Ohlins. Sucks being a big guy sometimes. along with the PCV and the Auto tuner
Currently the mechanic is hooking up the PCV and auto tuner, he is hoping to have it ready to run late tonight or early tomorrow morning. He is more excited about it then me I think. Well he gets to ride it first, tune it and set it all up before I get home. Wont be home until January. Spent my Bday, and will spend wife's Bday, Xmas and New Years in Abu Dhabi.... Lucky me. Thanks for looking. More updates to come.
For the price I paid for the stainless steel header and welding he can burn 1000 rods my total cost was equivalent to $50.00, you can find that in merica. Mechanic is all but done, after breaking in the engine and running the autotuner he found it was over fueling between 3000 - 4500 RPM. Thats all taken care of now. He says the bike pulls really hard now from idle to 11,500 RPM. I have been trying to get Jett Tuning to give me the un lock code for the rev limiter to bump it up to 12,500 RPM, but so far havent had any luck. He got all the little extras put on today. Slider & spools from T-Rex, fender eliminator from Yoshimura, and all the fairings back on. He is taking it to one of the tracks close by to home this coming weekend, and then he will take it to the local twisties road and dial in both maps. He mounted a switch on the bars to make it easy to swap between the 2 maps. The track map will be for of course the track and in town riding, the 2nd map will be for the higher altitudes for riding the twisties. Once I get home I get to start shedding the weight off the 250.
Ohlins rear shock installed, re-sprung for my weight
PCV and Auto Tuner installed
T-rex spools and slider installed along with fender eliminator
I should be home hopefully around mid January, cant wait to see how much different she will ride.
Made it home last night 1/15/2015, woke up this morning installed the 13T front sprocket, rear taillight with sequential turn signals took it out for my first test ride since all of the mods have been done. First impression..... SPEECHLESS!!! This is a whole new bike, I know 250 is small cc bike but you couldn't tell it from the grin showing through my helmet. With the bore kit and new cams this is a monster now. Really pulls hard from 8k to redline at 11.5K shift into second and the bike throws you back in the seat, first time I did it the bike tried to throw me off. The new suspension upgrade is like riding on a cloud, soft and smooth yet aggressive when you push it hard. I found a side street that was empty, pulled the front off the ground it friggin power wheelies now in first gear. No clutch up just roll off/on throttle and up it comes.
Weather permitting we will be taking it up the local twisty here tomorrow. Cant wait to really push it and see how it handles, I am sure she wont let me down. My little 250 will be going up against an RSV4, Ri & R6, cant wait to see the guys face when I pass them on the turns and pull away. They will kill me in the straights but no longer be able to do it so easily on the turns.
I am still waiting for my 42T rear sprocket to come in am sure it will be even better. Will post up pix later have to do a few things before that.
I am by no means a mechanic, Jeep we have a local mechanic that is a genius when it comes to motorcycles, doesnt matter the size. He build drag scooters that will give a 250 a good run. He is meticulous when it comes to his work. His specialty is suspension work, he goes to the track to ride and spends most of his time working on other persons motorcycles. The best part he guarantees his work 100% of course he charges a little more but well worth it.
Been a while since I updated this. We went out for a long 450 KM ride 1/2 of the ride is all twisties, I was riding my new CB1000R, my bro on his R1, my bro-in-law on the 250. We got about 150 KM into the ride and the wrist pin gave up. Towed it back to a local business they let me store it there for a few days until my mechanic could pick it up. After he tore it down, when the wrist pin broke, it bent the connecting rod, scared the bottom of the cylinder, and bent all 3 shift forks. Was thinking about just going back to stock 250, but decided to give it another try. bought a new 298cc JE piston, had to buy a crank shaft just to get the new connecting rod <---- that sucked, all 3 shift forks, and of course new gaskets. Mechanic finally got it all together and running again.Got the 250 home finally installed the 42T rear sprocket. This thing will now clutch the front end up and hold it up.
A little off topic, was at work in UAE, wasnt feeling good so went to local hospital. 17 days, 30 stitches, and an ostomy later, I am out of the hospital and finally back home in Philippines. Dr said not allowed to ride until ostomy is sealed back up so cant really update to much on the 250 performance. Once it was home and after installing the rear sprocket I did get to ride just a bit, the bike really feels much stronger. I am hoping to get the back to the track in November. Dr permiting of course. Will update once I have made it back from the track.
Yes came with Piston, and cylinder. Should have known better then to go with the junk they gave with the bore kit. So far so good using the JE Piston and pin. Had major surgery last August so havent been riding at all should be able to ride again this November. Will take it to the track and try to tear it up again. :wink2:
I was going to get the JE in the beginning but funds ran low at the time I was building it so I went ELCHEAP-O and ended up paying for the motor 2 times. I should have just waited another month until I had the money but my mechanic needed the room for other bikes he ws doing so I said WTF and used the piston and wristpin that came with the cylinder kit. At the time was just spending way to much on it.
Now it has the JE and everything seems fine, need to really push it once I am healthy again. If it blows the motor again I will just go back to stock and buy a Kawi 300 for the track.
I m back to normal now. Thanks for asking. The 250 is super sweet now. I have had it on 2 of the 3 tracks here in the Philippines, seems to be bullet proof now with the JE Piston in it. I have rode it harder then I should of and the motor just keeps giving. The bike now feels complete. Here is a 3 minute video of Myself on my CB1000R and my little bro on my 250. The little bike is a beast it doesnt have the power of a super sport in the straights but it will pass them on the turns. A lot of money well invested.
Great read, thanks. I won't be spending as much as you but will be upgrading suspension going forward. I love the Philippines BTW, I practice Arnis/Eskrima here in the states
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Honda CBR 250 Forum
228.4K posts
21.1K members
Since 2011
A forum community dedicated to Honda CBR 250 owners and enthusiasts. Come join the discussion about performance, racing, modifications, troubleshooting, maintenance, classifieds, and more!