spindoct

cant see the imageshak image bro.......

I've Herd that 510/18 can be too heavy for the rear mono shock and that the bike looses its handling due to the over size tyre i also herd that the big tire companies do not produce 510/18,only the Chinese and Koreans do...is there any truth in it...do you really loose the handling.... I need that original silent insert badly...its too loud for me..and im sensing that the lack of power is due to that...if any one could help me out...it will be great... Oh i almost forgot...im repairing broken digital speedometers..so if any of you guys have them...just let me know...

Can Any one tell me the standard Tire size for XR250R (1999) JDM,Front and Rear Plus im thinking of putting a new Chain Sprocket set so i also want to know the standard stock sprocket sizes If i go for a O-Ring Chain will i be not able to take out 9shorten0 the chain? With the WISECO piston and ring set dose it need any other parts to be replaced...?9since its liter than the normal piston) and i need the input on these...specially the part "GRINDING THE WELDED HEADER INLET" ------------------------------------------------------------------------------------------------------------------------------------------- MY MODIFICATIONS TO A 2000 MODEL HONDA XR400R (Revised: Nov 25, 2000) ----------------- Stock Carb Specs ----------------- Main 142, Pilot #52, Needle Clip in 3rd groove. Right off the showroom floor, mine ran fine, but definitely on the rich side. Removing the airbox snorkel without re-jetting, however, made it run lean and overheat. ----------------------------------------------- RELIEVING THE 2000 HONDA XR400R MUFFLER BAFFLE ----------------------------------------------- (This is a very simple procedure, and one that can be almost as easily reversed. Best of all, though... it works.) After carefully examining the stock baffle/spark arrestor, and running some flow numbers for the different areas involved with the numerous plates and baffles (both in the muffler and on the baffle insert), I've come to the conclusion that the primary restriction to exhaust flow is the small final outlet, which has an i.d. (inner diameter) of only 20mm. Without removing the baffle insert from the muffler, examine the exhaust tip. Notice the actual outlet, which measures 20mm i.d. (approx. 0.787"). Around this is a larger 'bright finish' ring which appears to have no real function, but may be to help prevent the rider from coming into contact with the actual outlet, which probably runs hotter. Down in between the 20mm outlet and the bright-finish outer ring, there is room to drill 1/4" holes into the baffle to provide additional exhaust flow area. Holes drilled in this area will be 'inside' the spark arrestor screen, by the way, so the spark arrestor function is maintained. On my baffle insert, the area to be drilled is large enough to accept a 1/4" drill, but there's a benefit to using a #2 drill bit (0.21") (or maybe a 7/32" bit) which I'll explain a little later on. Since the stock 20mm (0.787") outlet provides a flow area of only 0.4862 sq.in., and a 0.21" hole has a flow area of 0.0346 sq. in., each 0.21' hole adds 7.1% more flow area. Just three such holes will increase the exhaust flow area by over 21%, and four will increase it by over 28%. First I ran the engine with the undrilled baffle, to get an up-close feel for the sound level at idle, and while revving the engine. After drilling one hole, I could barely hear any difference. After drilling a second hole, I could hear the difference, but it was slight. The third hole made a bigger difference, but still not objectionaably loud. The fourth hole made it just a little louder than I was willing to accept, adding a definite bark to the exhaust note. Since I had use a #2 drill bit, which is approx 0.21" in diameter (it's supposed to be 0.221"), I was able to plug the 4th hole very simply by screwing in a 1/4x28 set screw, which I woudn't be able to do had I drilled the holes with a 1/4" bit. This effectively reverted back to having just three holes, and it also indicates that I can plug them all with 1/4x28 set screws, to return to the stock sound level if necessary. Come to think of it, I guess you could say that this modification is "tunable" by inserting or removing set-screws from numerous holes. A brief test ride with stock jetting showed that the added three holes gave the bike a cleaner and stronger throttle response, probably because it runs rich when totally stock. It was now running cleaner, so the added 21.3% flow area was beneficial, and it had cost me nothing but a little time. It's also totally reversible by plugging the holes with set-screws. It is NOT necessary to remove the insert when drilling each hole. The metal chips will fall either outside the muffler, or into the screened area of the spark arrestor. Once you have drilled the desired number of holes, you can then remove the insert and shake out the tiny pieces if you so desire. If you don't, they will eventually fly out the exhaust outlet anyway, since the spark arrestor screen prevents them from falling down inside the main muffler. --------------------------------- GRINDING THE WELDED HEADER INLET --------------------------------- I'd read about the header inlets being partially shut off by the welding that builds up when welding the 1" i.d. header pipes to the clamping flanges, so I examined mine. Simply loosen the clamp bolt where the header pipes assembly slides into the muffler, and then loosen and remove the four nuts (two per pipe) where the headers are clamped to the head. The muffler bolt and all four clamp nuts accept a 12mm socket. Then the header pipes assembly slides forward and into your hands. On mine, a 2000 model, the built-up welded area in each pipe was terrible! The remaining opening measured a rough 0.75", leaving a flow area of only 0.44 sq.in. A 1" i.d. pipe has a flow area of 0.78 sq.in, so the welding left only 58% of that! I started grinding down the built-up welds using small grinding stones in my Dremel Moto-tool, but that was too slow. I went to the hardware store and bought some inexpensive coarse grinding stones to fit my 3/8" drill, and one 1" ball stone for finishing. I spent over two hours grinding away. As a "size guide", I chose an 18mm socket that has an outer diameter of 0.944" (different brands will vary in size, of course). Once the 18mm socket would slide into the header pipe, I quit, not wanting to remove too much of the weld, and weaken the joint. I then used the 1" ball grinding stone to finish up. Since the stone itself wears away faster than the weld material, I ground a little on each pipe, going back and forth between the two, until enough of the stone wore away to fit into the opening. This final touch didn't really make either opening larger, but it did make them both about the same size and shape. Since I started with a 0.75" opening, which had a flow area of only 0.44 sq.in., and finished with a 0.944" opening, which has a flow area of 0.670 sq.in., I achieved a gain of more than 52.5%. In one afternoon I significantly improved the flow characteristics of the stock exhaust system, and my total investment was under $10 (for some cheap grinding stones and one 1/4x28 set screw). I already had the 3/8" electric drill and #2 drill bit. ------------------ AIR INTAKE SYSTEM ------------------ I removed the air box snorkel, and then used a scrap of aluminum window screen to cover the opening to keep out trash and clumps of mud. I then removed the stock air filter and support, the latter of which includes the backfire screen. Noting that the backfire screen consists of two layers of screen, between which are trapped two more layers (actually a flattened screen 'tube'), I carefully cut away only the outer layer of screen, and removed the trapped inner piece, leaving only one, the inner layer, of the original four-layers of screen. I happen to like foam air filters, so I'm sticking with the stock filter for now. (I later bought a TwinAir filter, but with the backfire screen modified, I see no performance difference between the TwinAir and the stock air filter. If I were using a louder and more free-flowing exhaust, perhaps the TwinAir filter would make a difference.) NOTE: Cutting the metal screen is a chore, and it's difficult to get rid of every tiny little piece of wire (from the screen) you cut, so I no longer recommend cutting the stock backfire screen. Intsead, buy a UniFilter air filter for the XR400R. It comes with a screenless air filter support, and a less restrictive air filter. Despite what I read elsewhere, it is NOT necessary to move or remove the subframe to remove the carburetor! After removing the seat and gas tank, I simply loosened the two clamps holding the carb to the airbox duct and intake manifold, then loosened and removed the three bolts holding the intake manifold to the head. By turning the intake manifold a little CCW first, the carb and intake manifold then slide easily out the left side. After removing the carb from the intake manifold, I examined the composite rubber & plastic intake manifold. I do not think it was necessary, nor do I think I gained anything from it, but I used my Dremel Moto-tool with a medium size sanding drum to clean up the few ridges found inside. Just couldn't resist! ------------------------- JETTING CHANGES REQUIRED ------------------------- After two days of trial and error jetting (and a few hours more since then), I came to find that the exact same jetting recommended by CYCLE NEWS (several years ago) worked best. I'm using a 160 main jet, a #60 pilot jet, and the triple-tapered carb needle that comes standard in the 1998 and later XR400R's, with the needle clip in the stock (3rd groove) position. My altitude is approx 700' above sea level, and I ride regularly up to 3200', where it still seems to work just fine. I've also replaced the 15t drive sprocket with a 14t. For the terrain where I ride, the stock gearing is a bit too high. Depending on your particular machine, you might prefer a 158 main jet is using a stock or modified stock exhaust. If using a louder and nmore free flowing exhaust pipe, or the 1996-97 spark arrestor without the muffler insert, you'll want to use either a 160 or 162 main jet. -------- RESULTS -------- How my XR400R might compare to a differently modified version, I don't know. All I do know is that it easily pulls away from an unmodified 1999 model, and that I am able to pull up the front wheel at will in any of the first 3 gears. It is a little louder than stock, but not as loud as a KLX300 with its muffler tip removed, and it is nowhere near as loud as an XR or WR 400 with the muffler insert removed altogether. It's more than I need for woods riding, but without being 'difficult' to ride. ----------------------------------- XR400R Spark Arrestor/Muffler Note ----------------------------------- The 1996/97 XR400R has a two-piece exhaust pipe insert. The removable spark arrestor has a removable muffler insert. With the muffler insert in place, the exhaust is very quiet and very restricted. With the muffler insert removed, the spark arrestor alone has an open outlet nearly 1.5" in diameter, so it makes really good power, but is also pretty loud. The 1998/01 spark arrestor insert has the small 0.787" outlet which serves as the combined spark arrestor and muffler, all in one piece. It has more restriction than the 1996/97 spark arrestor alone, but more restriction than the 1996/97 spark arrestor with the muffler insert. Both of the two different spark arrestors fit all years of the XR400R's exhaust pipe (three small bolts). Gordon Banks -----------------------------------------------------------------------------------------------------------------------------

"motor is revving perfectly and smoothly but the bike fails to achieve proper acceleration" (i think) this is the scenario,and it has a small fluctuation in rpm when in idle... well about the top end and the bottom end-In the top end im only able to reach a maximum of 100kmph in the road in front of "kala bhawana"stretch(i remember you mentioning you were able to reach speeds of 130kmph on yours),and in the bottom end, it dose not even lift the bike off the ground at least one inch (i know i bought a bike not a plane but still ) ,i know XR's renowned for their beastly torque,even my homey had a old analog meter XR which i had to think twice before i get on to it cos of its power plus theres a small fuel issue in it i think cos in my bike when i first cold start it and drives for about 2-5kms,when the engine is heated up(oil temp meter in the frame indicates 125c)i cant go in the traffic cos the engine stops unless if i don't keep on revving or i ride really fast...my garage dude said that the previous dude had cleaned the air filter with petrol,and that it is wrong to do that(i have the stock air filter[paper]) plus theres a tiny oil mark in the middle gasket in the head,garage dude also said that even the tiniest leak of compression is enough to bring the bikes power down...

well after i gave it a good carb, air filter cleanup and a tuneup from my garage it had a bit more torque...yes i know i cant expect the top end from a 4 stroke but its the laking bottom is what im more worried about.. and from my search on the net i fount couple of results saying that 48T is the stock,so now im quiet confused..

I have a small issue with my new XR250, i think my old DT200 is better than this,i mean this Xr dose not have any low end or top end,not much torque in bottom end,and the fastest i've ever hone is up to 100kmph is it due to the fact that it has a 42T rear sprocket and a 510.18 rear tyre? the stock muffler is open,no quiet insert in it,so there should be a bit torque than the stock isn't it?

guys i need some help,ok i found a XR a red one chassis number 150,oil cooled,in good condition, only prob is that idiot has cut the stock exhaust,only the middle insert is not there..outer chamber is ok.so i need some pictures of the end part for me to re build one...inside and out...not the chamber just the silent insert....please..can any one help me?

I'm really glad that this topic is revving up. ..and thanks for the all XR tips gyus ...that really helped me..yesterday wen i was in the net, looking for a XR, i came by this guy who claims to do heavy mods to 250cc and above bikes..especially after market silencer making... he said that hes making them for "performance,not for the beat" i cant post the link because its another SL site that ends with "lanka" Any how, the most recent test tail pipe I've made using S-lon for my DT using my friend's PRO CIRCUIT measurements has taken me to the speed limit of 140kmph,and 0-60 in just 3 gears..some times i even have second thoughts of shifting to a four stroke...i know i wont get that power hit like a 2-stroke,when you clutch it..but i guess I'd have to get satisfied with the torque and less maintainence..ha? I've also thought about those old XLR's or BAJA's being sold as XR's,Is there any way of detecting whether if tis a TRUE XR? i mean one can easily convert a new BAJA to a XR isnt it? anyways there used to be a small dirt track behind the waters edge,back when they were biulding the golf ground..me and my CRM friend used to go riding there..he is the one who dose D&D graphic decals....the stickers on my bike... My DT200R we are planning to go to pannala races..one of my female co-workers (sun fm) dad own the pannala track...lucky girl ha? So guys keep up the posting..its really good to see this thread active and moving forward...hopefully this would proceed to a gathering one day...

I've seen the super trap on most XR's...is it better than the usual after market exhausts like big gun,pro circuit,FMF? what dose the amount of discs used in the super trap has to do with? cos the XR im hoping to buy has a super trap..I'm more comfertable with the stock one..the guy said that he will me either one of them... and i would also like to know how much did it cost you,when you bought the XR...my budget is around 2.50 or less..and this dude told me that he's ok with it..its a red XR,oil cooled...Registration number is a "GN-XXXX"...Chasis number is 150,is it worth going for it or could there be something wrong in it for him to give it away at that price? any how I'm planing to take my garage guy there if im buying it.. all the other XR's i checked out were not fair for the price...all the red ones were above 3 and there not the straight rear fender type..one before..same as your one but red...and all the white one were around 2.50..so i thought what da hec..i could buy this red one for the same amount...

even my CRM friend has put on a pro circuit full silencer kit+boysen reed valves=k&n dual stage air filter...and its being tuned by chaminda at maradana(justin motors) now thats a monster..i had his bike for day...while he took mine to get some measurements...the stickers on my bike was his work.... any way,its ok to have speeds like 130-140 for few seconds right? i mean not to run long distances...yesterday one xlr250 (huge daka rally tank)bugger came to race with me in the traffic light..i thought he was gonna rip me away...but by the time i was on my 3rd gear he was way behind me... couldn't even see him so what are the usual repairs that come on the XR...and what are the usual maintainence tips...herd that the digital meter brakes down on most bikes..whats the solution for this..i checked the e-bay as well..they have some digital after market meters..plus if i want to get an after market silencer.where would i be able to get it? Oh by the way i have a 1989 DT200R - YPVS then came the DT200WR even after came the WR200R

Thanks bro for the info,yeah i know that i wont get the same out of a 4 stroke,thats what my friend who had a CRM250 also said...but the Honda trail bikes are like pit bulls..and i really like the design of the digital meter XR250...(but i have to agree with you..i don't like XR250 SM..i don't like the new rear fender...but as you've said i can expect more from the XR250..right? (Im hoping to buy a red XR- one before the straight fender models) I would also like know,whats the maximum speed you gone on your XR...and how is the engine doing at high revs....I've done 135Kmph on my DT200...

Thanks bro for the info,yeah i know that i wont get the same out of a 4 stroke,thats what my friend who had a CRM250 also said...but the Honda trail bikes are like pit bulls..and i really like the design of the digital meter XR250...(but i have to agree with you..i don't like XR250 SM..i don't like the new rear fender...but as you've said i can expect more from the XR250..right? (Im hoping to buy a red XR- one before the straight fender models) I would also like know,whats the maximum speed you gone on your XR...and how is the engine doing at high revs....I've done 135Kmph on my DT200...

ok this goes out to the guys who owns a XR250....i have a DT200R and ever since i got it I've been doing all sorts of moddings to it...after 3 years i think i had the best of 200cc..now im dieing to have a XR250...so any one who has a XR to sale please let me know...if its a red one it'll be great....my email address is [email protected] any thing related to Xr's...