Build Advice

[bkb88]

I have been doing research on which type of engine build I would like and I have decided on a 86mm Wiseco 10:1 piston for a baseline. I have already ordered the piston but I am still debating on a couple other items.
I am thinking about using a stage 2 Hotcam as well as a Sparks +6 key since I will only be running 10:1 compression. I'm not entirely sure on how the cam will perform with this piston so I wanted to make sure before I made any unnecessary purchases. Also, I was wondering if I should use the xr400 gaskets or just use a layer of RTV for a gasket to keep the compression close to advertised? I also have a crf450 timing chain on the list of things to buy. Any suggestions or thoughts on this build?

[CJM]

Id run a +3 key unless you want to run 100+ octane, some are ok with the +6 and pump gas-most are not.

Forum member wheelie makes the custom +3 keys several times a year-he may have some left, if not you can always wait a bit and he makes a bunch.

As for gaskets, XR400 is fine, dont use RTV. I myself have cometic brand gaskets due to the fact many feel (Im one of them) they seal and are way better than anything else.

Stage 2 cam will be fine with that setup.

[bkb88]

Do you think it would run well with the +6 key if I used E85? It is available at nearly every gas station around me. I thought, from what I had read, that a member with the username tri5ron ran a +6 key, stage 2 cam, and a 10:1 Wiseco piston with no issues. I think the only difference with his was that he used an 87mm piston. Thank you for the extremely quick reply.

[CJM]

It depends on the elevation, temps (both the bike and the area your in) and the exact setup you have.

E85 will def work better-you need to rejet it to run E85 tho.

[bkb88]

The average elevation for my area is around 381ft. The average temp around here is 90-95 in the summer with a heat index of 100-110. Will I still be okay running E85 with the cam & sparks key at this elevation and temp range?

[2001400exrida]

bkb88,

Do you ever go to Little Egypt Off-Road?

Went there about a month ago and it was fun times! We are heading to Turkey Bay at the end of this month.

Cometic sounds like the way to go with the gaskets. I personally bought Tusk from Rocky Mountain and, although i only have about 2 hrs total on machine, they are holding up so far.

[CJM]

Should be.

Worst case you yank out the sparks key. Would be a good idea to get an aftermarket larger oil tank and a spal fan to help keep everything cool tho.

[bkb88]

2001400exrida,

I have not been to the little egypt OHV park yet but I have always wanted to go. I'll definitely have to check it out once I get my 400 back up and running. I'm jealous...I want to go to turkey bay! lol. I think I'm going to give the Tusk gaskets a try as well. Everything else I have used from them has been really high quality.

CJM,

So for the $30 key it's looking like it's going to nickle and dime me to death with other components to keep it running correctly. Do you know of how much extra performance it will even give me if I ran it in conjunction with the cam? Might stay away from the +6 and go for the +3 if it's not going to be a noticeable difference.

[CJM]

I dont have a key, I have:416cc, 11:1 stage 2 hotcam, its jetted right, a good slip on/custom modded stock header, and such-nothing to insane. But of course mines a bit more built up than most too. I also have a spal fan I can flip on incase I feel its to hot and Im putting on a larger oil tank and eventually larger oil cooler. Temps in the summer here can be 90+ and I run pump 93.

I know a few guys run the +6 or +3 key with 10:1 and dont have any issues, but everyones quad, the area they ride in, riding style, etc might be different ya know? I personally wouldnt want to risk it or pay the extra money for higher octane gas (93 pump is already 4/gal! and 100 by me is 8/gal!)

You wont be unhappy with a 10:1 either. More compression means more power. I always try not to overbore a bike, just raising the compression is enough-thats why you hear so many think the 440 is great-till they find out it just aint as fast as they thought compared to a 416 or 426. More compression=more power.

What the timing key does is it advances the timing, firing your spark plug at true top dead center. Thus creating more heat-400ex is air cooled, heat=bad. If the EX was watercooled I dont think it would matter.

Sparks says right on the site not to use with high compression too. On a stock bike its quite a noticeable gain. On a high comp piston bike you will find you get detonation (pinging) which is bad and its not really helping all that much.

See this for more info:http://www.exriders.com/vbb/showthread.php?threadid=455151

If your gonna run a key do wheelies +3 key and be prepared to run 100+ octane if need be. Good luck with it man
:)

[AtvKid4Eva]

I know with gas prices where they are i wouldn't want any ATV that requires race gas lol. Id just do the piston and a stage 2 hotcam and trust me it will wake a stock 400 up! You could always do a 450r carb too which is a cheap mod with good performance gains. good luck man.

[2001400exrida]

i'm more concerned about my vehicle as far as gas prices go.

I really don't mind paying $4.50 a gal. for 100 octane.

I just feel better, it smells better, and my 11:1 just loves it!

[AtvKid4Eva]

ha not me. Theres no advantage running that 100 in a 11:1 might as well just throw money out the window lol. Does smell good tho!

[2001400exrida]

My advantage is a cooler motor. 11:1 air cooled machine likes 100 octane. 93 would work yes, but 100 works better!

now, the liquid cooled 450's are 11:1 too and they run 93 just fine, but again, on my air cooled ex which heats up easily, i prefer to run 100 octane.

i'm not here so start an argument but i'm telling you straight up.

[bkb88]

Thank you guys so much. This has answered my questions thoroughly and very quick I might add.

So here is my build plan:
10:1 Wiseco 86mm piston
Stage 2 Hotcam
Crf450 timing chain
Xr400 Gaskets
Xr400 right crankcase cover

-I'm still debating whether I want to mess with the E85 + the sparks +6 key due to the drastic jetting changes that would need to be made. I might just opt for the +6. I'm just trying to get the best bang for the buck on these mods and still be able to survive the heat & humidity of Southern IL during the summer
:ermm:

-From what I have read, the 450r carb is one of the most cost effective mods available. How far off is the jetting on these carbs when they are on their stock settings for a stock 400ex engine? Also, do they use the same style hex main jet that the 400ex carb uses?

[CJM]

Your call on the key, do it if you want-up to you in the end.

As for the jetting of a 450r carb, usually its not to drastic vs your stock carb. 04-05 450R carb uses same jets.

[IMSROLL450R]

Originally posted by bkb88
Thank you guys so much. This has answered my questions thoroughly and very quick I might add.

So here is my build plan:
10:1 Wiseco 86mm piston
Stage 2 Hotcam
Crf450 timing chain
Xr400 Gaskets
Xr400 right crankcase cover

-I'm still debating whether I want to mess with the E85 + the sparks +6 key due to the drastic jetting changes that would need to be made. I might just opt for the +6. I'm just trying to get the best bang for the buck on these mods and still be able to survive the heat & humidity of Southern IL during the summer
:ermm:

-From what I have read, the 450r carb is one of the most cost effective mods available. How far off is the jetting on these carbs when they are on their stock settings for a stock 400ex engine? Also, do they use the same style hex main jet that the 400ex carb uses?

Id recommend an FCR over the 450r carb anyday. There really isn't a comparison, the 450r is better than the stock 400 carb for sure but is light years behind the FCR as far as throttle response is concerned. I just put one on mine and was amazed at how easy it was to tune.

[Thumpin]

I run a 416EX 11:1+ compression with a +6 Sparks Key and HotCam2, it runs cooler now on E85 than it did stock with pump gas! Been running it for 3 years now and love it!

The trick is to get the jetting correct, and the needle was the toughest to get right, buy a Duncan or CT racing needle that has richer tapers, use the bottom clip positions, than use a 48-50 pilot and jet the main in the 190-200 range. That should get you real close on a stock carb with K-jets.

Right now I'm talking with Charlie Rossier from Rossier Engineering about switching my Can-AM DS450x to a 13.8:1 piston running E85, he says he found that combo ran cooler than stock also, I'm on the E85 wagon and ready for a cool powerful ride!

[bkb88]

Thumpin,

Thank you for your input on your experience with the E85/+6 key combo. I will definitely be looking into upgrading to the +6 later on after I get more cooling upgrades for my motor. Summer is just around the corner and I believe that the +6 will be too much for my 400 to handle with stock cooling combined with the 95+ degree heat that is on its way.

Here is my final build list:
86mm 10:1 Wiseco Piston
+3 Key
Stage 2 HotCam
XR400 Top-End Gaskets
XR400 Clutch Cover
CRF450R Timing Chain

Can someone take a stab as to what a good starting point for jetting would be using 93 Octane?

I just got my cylinder & head back from the shop...I'm speechless as to how good of a job they did! I had both my cylinder & head bead blasted and had the cylinder bored & honed for only $100. They also inspected my ring end gap clearances.
:)

Here are some pics:
http://i100.photobucket.com/albums/m14/thebutelr/SANY0404.jpg
http://i100.photobucket.com/albums/m14/thebutelr/SANY0403.jpg
http://i100.photobucket.com/albums/m14/thebutelr/SANY0402.jpg
http://i100.photobucket.com/albums/m14/thebutelr/SANY0401.jpg

[bkb88]

Anyone have suggestions as to what jetting I should start out with for 93 octane fuel? I was running a #155 main with a #40 pilot jet and my only mods were ground header welds with an HMF slip-on.

I'm just trying to get an idea so I can buy a range of jets to have ready once this rebuild is complete.

Also, what is the recommended size of spal fan to install on a stock oil cooler? I have seen people running 4" puller fans but I cannot find any on Ebay. The only ones on there ATM are the 5.6" puller fans. Would these fit on a stock cooler or would it get in the way of the tank shield?

[CJM]

Id say 168 (maybe 165) main, 40 or 42 pilot (try the 40 since you have it), and 2.5 turns out the a/f screw.

[bkb88]

CJM,

Thank you for your reply. I will be buying a range from mid 160's to low 170's. I'm just worried about getting this within safe jetting range for the first few runs on my new top end.

The part that I'm most excited about having on this build is...

THIS!
http://i100.photobucket.com/albums/m14/thebutelr/SANY0415.jpg
:)

I'm planning on painting the crankcase gloss black but I need some ideas for what color I should paint the filter & clutch covers.

[Rip0000it]

What is the bennifit on XR case? Something to do with the clutch right?:confused:

[CJM]

Originally posted by Rip0000it
What is the bennifit on XR case? Something to do with the clutch right?:confused:

You can remove the clutch with ease, that middle cover bolts on/off instead of taking off the entire side case.

I recall you need to extend the top of the clutch arm (that goes to the cable) and possibly use an XR basket or hinson or similar.

[bkb88]

CJM,

I put the cover on to test the fit and it went on with no problems. It is no different than a stock cover in regards to clutch basket clearance. My cover came with the clutch cable arm and it is slightly longer than the 400ex arm but it isn't very noticeable. This cover came off of a 1996 XR400.

[CJM]

Originally posted by bkb88
CJM,

I put the cover on to test the fit and it went on with no problems. It is no different than a stock cover in regards to clutch basket clearance. My cover came with the clutch cable arm and it is slightly longer than the 400ex arm but it isn't very noticeable. This cover came off of a 1996 XR400.

That confirms my suspicions that when originally this idea came up and someone did it-he lengthened the arm slightly about a 1/2 inch. However the XR one should (and was an idea before) to work. Now its confirmed.

http://www.exriders.com/vbb/showthread.php?s=&threadid=453638

[CJM]

btw, what did you use for the seal for the kick start?

[bkb88]

I ended up taking the cover to a shop to have a piece of aluminium welded on the outside of the hole. The case is at my local painter and should be done by the beginning of next week. I'll post pics as soon as I get it installed.

I think the reason the guy had to extend his actuator arm is that the Hinson cover looks to stick out farther than the OEM XR400 cover. I'm not 100% on this but that's what it's looking like from the pictures I've seen.

[CJM]

Im thinking I could get away sealing one up with some washers, nuts, a bolt and some RTV. Course putting the bolt head in the inside-to risky to put the nut on that side.

[bkb88]

Yeah you definitely wouldn't have to go the route of welding it completely shut like I did. I was originally going to use a plug like what came stock with the 2006+ TRX450ER's for the kick start holes. The dimensions of the 450ER plug was unfortunately 28mm while the kick start seal for the XR400 is 29mm.

I was thinking that I might be able to get away with putting the 28mm plug in and use RTV to compensate for the 1mm difference but I decided that I didn't want to have it possibly fail while out riding so I just had it welded.

As for the kickstart arm question, here are some pics comparing the 400ex arm to the XR400. I think there is only a 1/4" difference between the two. This is what came with the clutch cover so I am assuming that this is what was originally for the XR400.

XR400 on the left. 400EX on the right.

http://i100.photobucket.com/albums/m14/thebutelr/SANY0426.jpg

[CJM]

Good info, the other guy had added a 1/2" but I think 1/4" should be ok-we shall see when you get it all done.

[bkb88]

Well guys I ran into some trouble with my XR400 cover... It seems that the slot for the cover is angled to the front of the bike instead of straight up and down. This causes the clutch arm to travel farther forward than the 400ex side case. This makes the 400ex clutch cable far too long. I have the cable adjusted all the way to the end and it is finally where I can get tension on my clutch lever. Anyone know of a shorter cable that would work??

I had to modify the 400ex clutch bracket to make it fit on the xr400 case as well. Does anyone have any experience with heavy duty clutch springs? Are they supposed to be incredibly hard to pull?? If not, I believe I have an issue with how my clutch was installed. I will try to put my stock springs back in to see if they make a difference tomorrow.

[bkb88]

Update: I have some bad news on the xr400 side case... It turns out that not only is the 400ex clutch cable too long for the stock xr400 outer cover, the cover itself is actually too shallow to allow for the lifter arm to work properly.

Looks like for this to work, the xr400 basket assembly will have to be used. :( . I guess I'm going to have to throw my old stock clutch cover on for now until I figure out exactly what parts I will need...

[bkb88]

Sorry for all the posts guys but I have another question haha. I got my 400 up and running this morning but only ran it for maybe 30 seconds. I noticed that the idle was really fast as soon as it started up. Other than that it sounded great, no weird noises or anything.

Could this be from the jets I installed for the new mods, throttle cable, or idle screw on the carb? I installed a 180# main, 42 pilot, moved the needle clip one down from stock, and I am not running the air lid. I will definitely be jetting down from the 180# main after break-in but I want to be absolutely sure I will not be running lean.

[CJM]

My idle always need to be slightly turned up when I first start it-then I can crank it down or leave it alone. Id say your throttle cable is adjusted to tightly in the lever, opening the throttle slightly. Also check the idle screw of course.

As for jetting, Id say if youdid an 86mm 10:1 and such your gonna be about 162 as a good starting point. 180 is way to rich.

[bkb88]

Thank you for the suggestion, it was indeed the throttle cable lol. I dropped my main back down to a 170 for break-in and I had to actually move the needle back to the stock 3rd from top position. It was bogging past 1/4 throttle. There is also a slight pop occasionally on decel. Maybe some more tweaking with the air/fuel screw on the 42 pilot?

Also I came across a complete used stock 1996 xr400 setup for really cheap! Judging from the pictures it was in excellent condition and the seller had a very high feedback rating. I'm crossing my fingers that this will enable me to finally use my nice removable clutch cover :). If this does not work I will be completely out of ideas as to how the bottom end could be any different than the XR.

[CJM]

Yea, slightly lean on pilot circuit. Change it to 2.5 turns out and go out a 1/4 turn from there. Mine is about 3 turns out.

[bkb88]

Okay now I'm getting angry... Looks like my tusk gasket kit has turned out to be complete crap. I have maybe an hour on this top end at most and now I am seeing oil seepage around the head :mad: . I could see little air bubbles forming along the head gasket on the flywheel side of the motor.

I double and triple checked the torque settings on every bolt on this motor before fully installing any section. I made sure and torqued the head in three steps in a criss-cross pattern: 15ft lbs, 25 ft lbs, and finished with 33ft lbs. Is this probably due to a poorly made head gasket?? Everything else from tusk I have has been great so I figured it would be the same with gaskets...guess I was wrong.

[CJM]

Could have an imperfection in the head/cylinder?

But Id just say junky gaskets. Shame cause several others have used tusk and had no issues. Me, I like cometic or OEM. Something to be said about the cometic tho-its multi layer steel gaskets with a viton coating-they actually adhere to your parts-had a hell of a time taking my topend apart a few days ago-but worth it due to the seal they make.

[bkb88]

Well I fixed the head gasket issue. It ended up being a bad gasket (Tusk). Replaced it with an OEM XR400 gasket and haven't had any problems. I also went ahead and put in new OEM valve seals to make sure that the Tusk seals weren't going to fail prematurely.

I now have a new issue. I have around 2.5-3 hrs on the top end and I can see a faint hint of blue smoke after I give it a good rev in neutral. I followed the break-in procedure on this (http://www.mototuneusa.com/break_in_secrets.htm) site. The smoke starts out black then fades to a blue/white color when I let off the throttle. About how long does it take to seat the rings? I had the machine shop bore & hone the cylinder to match my new piston as well as check the ring end gap for me. I also made sure and staggered the rings exactly as the Wiseco diagram showed. I lapped the valves while I had it apart as well.

Any ideas? :confused:

[CJM]

Could just take a bit, could also be to rich which will seem like blue smoke. Check your plug.

[bkb88]

I have performed a plug chop with a brand new plug and I have no color on the porcelain even down to the bottom. I am currently running a 165 main, 3rd clip on needle, and a 42 pilot. What in the world could cause this to not have any coloration? I ran through the gears to 3rd (not much room for higher gears) and held it WOT for about 5 seconds then simultaneously pulled in the clutch & kill switch.

Here is a pic of my plug after the run.
http://i100.photobucket.com/albums/m14/thebutelr/SANY0478.jpg

I can't even see a trace of brown by looking inside so I will not cut up this plug until I figure out what is going on.

Should my plug look something like this (http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/) when it's jetted right? The pics are at the bottom of the post.

[bkb88]

I went ahead and cut the threads off of the spark plug and it is white as snow...

http://i100.photobucket.com/albums/m14/thebutelr/SANY0484.jpg

Am I missing something here?? :confused:

[CJM]

Id say its probably lean, but it could just be it wasnt in there long enough to get any color.

I basically slap a plug in and go riding around my yard a bit and see whats up, maybe load the engine a bit. In 10mins the plug has run thru most engine rpms and is usually pretty accurate.

[honda400ex2003]

Originally posted by bkb88
I have performed a plug chop with a brand new plug and I have no color on the porcelain even down to the bottom. I am currently running a 165 main, 3rd clip on needle, and a 42 pilot. What in the world could cause this to not have any coloration? I ran through the gears to 3rd (not much room for higher gears) and held it WOT for about 5 seconds then simultaneously pulled in the clutch & kill switch.

Here is a pic of my plug after the run.
http://i100.photobucket.com/albums/m14/thebutelr/SANY0478.jpg



I can't even see a trace of brown by looking inside so I will not cut up this plug until I figure out what is going on.

Should my plug look something like this (http://www.blasterforum.com/do-yourself-20/how-plug-chop-38674/) when it's jetted right? The pics are at the bottom of the post.

that pic looks lean to me. id go up 1 size for sure, probably 2. i just saw one like that today as a matter of fact. I went back up 2 but will be trying 1 up soon. i might be back at 2 though after a test run on it. lol

steve

[bkb88]

Thank you for the replies guys. I have been doing a lot of research on this topic and I have found that plug chops are really not viable for bikes running on pump gas. I have read on multiple forums that the pump gas we have today has a lot of detergents and will not give an accurate reading like it would if running leaded race gas. I'll bump up the main to like a 180 and see if I still get any color just for kicks. If it doesn't I am just going to rely on trail and error as to how the bike "feels" with different jetting settings.

I will be doing the next plug chop on an open stretch of road and make sure to hit 5th WOT and hold it for a few more seconds. I have noticed that ever since I moved the needle clip to the fourth position that my power has felt rather "flat" and doesn't have the "kick" it used to.

What's weird about the plug reading white is that I am puffing out black smoke. :ermm:

[bkb88]

I just went for a run on a back road around my house and this is what my plug looked like after installing a #180 main...

http://i100.photobucket.com/albums/m14/thebutelr/SANY0495.jpg

Notice the flaking going on at the tip of the plug... This is making me think I have an air leak somewhere around my intake or in my exhaust system. The picture makes the tip look brownish but let me assure you it is very grey. There still is no coloring on the plug as was before. Any ideas??

[honda400ex2003]

the end of the electrode will only show you if the heat range is correct on the plug. it looks like the heat range on it is fun but still looks a bit lean. one more size would probably do it for you imo.

steve

[bkb88]

Set aside the jetting for a moment... Have any of you ever seen this happen???

http://i100.photobucket.com/albums/m14/thebutelr/SANY0497.jpg

This happened while trying to remove the drain plug out of the oil tank. I always torque this plug along with every other nut/bolt on this 400 to the correct specs so I know it wasn't over-tightened. It completely took the threaded insert with it:eek: . Looks like I'll have to finally buy a CFM oil tank. Do these use the stock hardware? Also, how is the fit with one of these installed?

[honda400ex2003]

thats pretty hard core man. ive never seen that come off :O lol steve:eek2:

[bkb88]

I know man I though this was pretty odd...FML lol. :p

[Rip0000it]

[QUOTE]Originally posted by bkb88
[B]Set aside the jetting for a moment... Have any of you ever seen this happen???


O ya my buddy did the same thing!!!!! We went to the parts store and got a expandable plug. Works great and no leaks.

[chronicsmoke]

Originally posted by bkb88
This happened while trying to remove the drain plug out of the oil tank. I always torque this plug along with every other nut/bolt on this 400 to the correct specs so I know it wasn't over-tightened. It completely took the threaded insert with it:eek: . Looks like I'll have to finally buy a CFM oil tank. Do these use the stock hardware? Also, how is the fit with one of these installed?

Happened to me about 6-7 years ago, I was able to get it welded back on by a machine shop.. cost me like 20 bucks and it's been good since.. Just took the bolt out again last night too lol

[bkb88]

I just got my new CFM oil tank installed and man is it a tight fit! I am very impressed by the quality of the tank. :)

http://i100.photobucket.com/albums/m14/thebutelr/SANY0552.jpg

I figured if I was going to install a larger oil tank, I might as well make it complete with a SPAL fan! I shouldn't ever have to worry about cooling issues for as long as I own this bike haha.

http://i100.photobucket.com/albums/m14/thebutelr/SANY0553.jpg

[Speed37]

i know its an old thread but wow!! Is your tank touching your flipping head pipe????

[CJM]

I have the same tank, its VERY close to touching. It slike 3/16" away form the pipe, Im sure his is closer b/c the headers wrapped.