New TRX400 Owner with Heating Question

[nevadatrx400ex]

Just bought a 08 trx400, am new to quading , really like it. I hope I chose right with trx400 since I'm getting older and dont want to race but like to ride trails, taking it easy but also like to punch the throttle on straight stretches , I think the trx will fit the bill on tight trails.
But my question is: when I'm in tight technical trails going slow in 1rst gear, the motor seems to get hot. are these motors sufficiently cooled with just the oil cooler? anyone have any problems? I do live in Nevada and it can get up to 95+ degrees on a riding day and that engine seems pretty toasty when donw. should I be concerned? it seems to run really well. lots of low torque. Nice comfortable ride.

[quadrider00]

i would start with an XR's only temp dipstick so you can see the oil temp. then a set of air scoops from UM or OMF.
and if your still running too hot you can hook up a 4" spal fan on the oil cooler... alot of people do this there is even a sticky on how to do it

[nevadatrx400ex]

where do you get the fan? there's no problem sucking too much juice fromt the battery? and it has installation kit & instructions to mount on the trx? I'll check on the air scoops, so they really make a difference? I can see the fan working.

thanks for the info.

[quadrider00]

spalusa.com or ebay for the fan. the fan doesnt come with instructions for the trx but in the 400ex section on here the is a good write up on how to mount it... it is a sticky at the top of the section
the charging system will be able to handle the fans load no problem and the scoops do help direct more air over the motor and cooler

[nevadatrx400ex]

does the fan turn on and off with a thermostat or does it run continously?
Do alot of folks use these mods? have there been people on this site who have "cooked" their engine oil and cause damage from riding slow on hot days?

thanks

[tri5ron]

Originally posted by nevadatrx400ex
does the fan turn on and off with a thermostat or does it run continously?
Do alot of folks use these mods? have there been people on this site who have "cooked" their engine oil and cause damage from riding slow on hot days?

thanks
here's some good reading
http://www.exriders.com/vbb/showthread.php?s=&threadid=391138

scoops do nothing at low speeds, and only provide little more airflow ,at best, over the cylinder head at higher speeds. they are not a cure-all for heat. a temp gauge and attention to it, is your best bet.
on a stock bike, (stock piston and compression), you don't have to worry too much about it. just pay attention to what your doing, and you'll be fine.

most heat related failures are associated with higher compression and large bore mods, and sometimes too lean of A/F jetting mixtures when changed from stock.

[TRXRacer1]

Originally posted by quadrider00
then a set of air scoops from UM or OMF. I bet those air scoops work real well when going slow in 1st gear.

[quadrider00]

every bit of air helps and im sure he will make it out of 1st gear

[nevadatrx400ex]

I made it to second gear once

[quadrider00]

o wow then you can probly 86 the scoops lol

[IcutMetl]

One thing I did when I got my 400ex is switch to synthetic engine oil after I got it broken in well. I switched to AmsOil 10w40, and I noticed it ran a bit cooler. I'm sure a good synthetic will also help protect better at higher heats.

[TRXRacer1]

Do you have any intake or exhaust mods? It's possible you might need to richen up the jetting a fuzz too. Even stock can use a little work.

[Snipe]

If your never gonna make it out of first gear then I dont think you would have to worry about heating issues at all.

[nevadatrx400ex]

Maybe I didnt get my point across, I was riding with a friend on trails for 3 hours and was running all out quite a bit of the time and most of the time was running at a good clip but for about 30 minutes we got off on a trail that got worse and worse through big woops and eventually navigating through football size rocks for 1/2 mile to get to the top of a hill to look over the valley and being 90+ degree day, it seemed to be getting warm but then again, I am new to this and maybe that was normal and the quad ran great all day. I simply posted question to get some feedback. I dont plan on riding bad trails like that again.

[TRXRacer1]

Originally posted by TRXRacer1
Do you have any intake or exhaust mods? It's possible you might need to richen up the jetting a fuzz too. Even stock can use a little work. Still a good question. Do you know what your jetting is?

[IcutMetl]

I think you made a really good choice of 4-wheelers- the 400 is easy to ride with no surprises, fast and powerful enough for most anything, and is relatively easy on fuel. Granted, I'm from Ohio and don't have to deal with the Arizona heat, but there wasn't a time I took my 400ex out that I didn't hammer the piss out of it...hot or cold...and it never let me down. 400ex's have a near-bulletproof motor; even for being air cooled- take care of it well and it will last you a long time. General maintenance will go a long way; keep the air filter clean, change the oil & filter regularly, check the valve adjustment every couple of oil changes, keep everything lubed & clean, etc. I'm sure you'll be more than fine, but this site is a very valuable resource- especially if you are interested in modifying you 'wheeler. If you're not a mechanical person, its still nice to be aware of what's out there for you.

[Ryanwolfe911]

Originally posted by tri5ron
here's some good reading
http://www.exriders.com/vbb/showthread.php?s=&threadid=391138

scoops do nothing at low speeds, and only provide little more airflow ,at best, over the cylinder head at higher speeds. they are not a cure-all for heat. a temp gauge and attention to it, is your best bet.
on a stock bike, (stock piston and compression), you don't have to worry too much about it. just pay attention to what your doing, and you'll be fine.

most heat related failures are associated with higher compression and large bore mods, and sometimes too lean of A/F jetting mixtures when changed from stock.

Agreed. A bone stock motor will almost never overheat, even in 100 degree+ temps. I live in Colorado, and I have had my quad out in the desert plains on 95 degree days and had no issues at all. Yes, you can feel quite a bit of heat coming from the engine, but it's no cause for concern, unless you feel that it's getting REALLY hot. Like, hot enough to cook a steak on.

[nevadatrx400ex]

Thanks for all the great input. the bike is completely stock and will remain that way engine wise. I have ordered a skid plate and a larger fuel tank and am thinking of adding a rear rack to tote a small cooler or whatever.

[tri5ron]

post up some pics of your new toy.

[RIDEREDson]

I'm surprised noone has told you this yet.

If I was you, All I would do is run a 20w 50 synthetic in it. It will keep it cooler on them 95+ days. I ran Mobil 1 15w 50 and it made mine run alot cooler. No need to rig up the spal fan.

[tri5ron]

do some search's and reading on the synthetics before putting it into your quad. Then make your own decision, reguarding the use of synthetic oil.
Alot of debate on it here about it, any many claim that they have no problems with it.
BUT, your 400EX has a wet clutch, and anything with Moly is not recommended, due to it can cause clutch slippage.

Do yourself and your quad, the best favor possible.
Buy a Honda factory Service Manual.
It is your best friend.

You have stated that it is going to be used for trail riding, and that you are going to keep the engine basically stock.
(same as my quad, with only minor mods).
I'm assuming that your reasons for this, is to maintain as much as possible, of the proven reliability, the 400ex has to offer.

If this is correct, then you and I are in the same boat, and have no intrest in trying to beat a 450r.
(a common obsession with many of the younger riders), and as a result, things like huge bores, high compression, and aftermarket rev boxes, are constantly debated.
(none of which, the 400ex takes to, too kindly , and they come with a host of reliability related issues).

Of coarse,this is all just MY opinion,...
and you should read, learn, and form your own.

As I had told you in a previous post, Consider the source of info derived here, do your reasearch, and make your own informed decisions.
remember that,... and your quad will run reliably for many years.

[nevadatrx400ex]

your right there.
I have no interest in racing other quads, jumping it, climbing super steep hills or anything like that. just want to cruise forest service roads and check out trails along the way and keeping it stock. the 400ex sure handles nice and rides smooth. very happy riding it with my out of shape rear end. am not a big mechanic but am capable of changing my own oil regularly and cleaning the air filter. dont have a serice manual for it yet. whats a good conservative estimate changing oil after how many hours operation? I have never been big on synthetic oil, just use good qualitly oil and change it regularly.
what mild mods have you done?

[RIDEREDson]

Originally posted by nevadatrx400ex
your right there.
I have no interest in racing other quads, jumping it, climbing super steep hills or anything like that. just want to cruise forest service roads and check out trails along the way and keeping it stock. the 400ex sure handles nice and rides smooth. very happy riding it with my out of shape rear end. am not a big mechanic but am capable of changing my own oil regularly and cleaning the air filter. dont have a serice manual for it yet. whats a good conservative estimate changing oil after how many hours operation? I have never been big on synthetic oil, just use good qualitly oil and change it regularly.
what mild mods have you done?

For your type of riding, I would do every 15-20 hours.

I was just sting that running a heavy oil weight will help keep it a little cooler. Instead of rigging up a fan.

[Ryanwolfe911]

I agree again. I don't understand what people's obsession is with wanting to beat 450's. I knew it would take way to much work and money, and make my 400ex much less reliable (which is it's best feature) so I just bought a damn 450R. I couldn't go wrong, I got a really nice totally stock '05 for $2400. I would have spent way more than that trying to make my 400ex even half as fast as a 450R with minor mods.

Made much more sense to just buy another quad, and the added benefit is, well, I have another quad.

I really like my 450, but for forest service roads and technical trails, I'll always pick my 400ex first.

[tri5ron]

Originally posted by nevadatrx400ex
your right there.
I have no interest in racing other quads, jumping it, climbing super steep hills or anything like that. just want to cruise forest service roads and check out trails along the way and keeping it stock. the 400ex sure handles nice and rides smooth. very happy riding it with my out of shape rear end. am not a big mechanic but am capable of changing my own oil regularly and cleaning the air filter. dont have a serice manual for it yet. whats a good conservative estimate changing oil after how many hours operation? I have never been big on synthetic oil, just use good qualitly oil and change it regularly.
what mild mods have you done?
Well if you think it rides nice now, you'be AMAZED once you do a few of what I call "Best bang for your Buck" mods.

First and Foremost,...
The one thing ,that Honda really dropped the ball on, with the 400EX, is the front shocks.

They have no compression or rebound adjustment, the springs are a harsh single rate, the preload adjustment is from the '70's, and is basically useless. Bottom line is they SUCK.
We commonly refer to them as "Pogo Sticks".
Sure the bike rides ok, ... and for trail riding they are barely sufficent.
You'll basically be "ignorantly pacified" with them, until you ride one with better shocks.
After that, you'll be saying,
"I gotta lose those pogo stick pieces of junk immediately".

The most cost effective way to make a HUGE difference, is to watch ebay for a good deal on a set of 450r front shocks, and then buy a set of Works dual or triple rate springs for the 450r shocks.
(the oem springs on the 450r shocks, are a bit harsh on the 400ex, due to the 400ex has a slightly shorter a-arm). And since you are a TRAIL rider, you dont want or need to go with longer a-arms. (hey !, saving you money right there!).

You CAN take it a step further, and send the 450r shocks TO Works, and have them re-valved to your weight and riding style, but I've found that to really be unneccesary.

I have a set of new 450r's with a Works triple rate spring set up, using the 600/600/215 spring rates, NOT re-valved,...
and the difference in ride quality is akin to a wild bronco vs. a limosine.
YEAH,.... it's THAT much of a difference!

Don't worry about the rear shock, they actually did a decent job with that one being stock. Sure it can be upgraded too, but again,.. it is unnecessary.

Second thing to do,...
and to compliment the new front shocks,...
is a good Steering Stabilizer.

You can get into all kinds of debates as to what is best, who has what, this is better than that, stick vs. puck, brand vs. brand, etc., etc.,.....
But we're talking "Bang for your Buck" here.

I'm not going to go into all of the reasons as to which rates over one or the other. rather, you need to go read this thread, listen to what many have said there, (including myself), and make your own decision.
(my dollar to your doughnut says, I know what that decision will be,... LOL!) Read all 11 pages, it's a fun read, and a crack-up.
http://www.exriders.com/vbb/showthread.php?s=&threadid=349366&highlight=custom+steering+stabilizer

Third thing to do, (if you dont already have them),....
NERFS WITH HEELGUARDS,
a-arm,... frame,... and swinger skids.
(you already mentioned that you ride in rocks), (Me too).
Go ahead and toss in some good hand guards to that little salad.

So now that we've got you riding like a "Armor Plated Limosine",...
lets make a little more power, while not infringing on, or compromising the reliability of the 400Ex.

Your stock exhaust, airbox, and airfilter, is restrictive.
nice and quiet, Yes,... but very restrictive.
We can go into HUNDREDS of pages, threads, debates, and opinions, on this subject as well.
But the reality of it is, ALL aftermarket exhaust systems, coupled with a better airfilter, and a properly re-jetted carb,...
will give a noticeable gain in performance and throttle responce.

lets face it, they are ALL WAaaay overpriced. from slip-ons to full systems. Why are they so overpriced???
Because they are the most easiest, most marketable, most commonly desired modification second to none.
You dont think the manufacturers are unaware of that fact do you???
It's all supply and demand.
They have the supply,...
They PROMOTE the demand...
we suck it up.... and hand over our $$$. That's the way it is.

But for a little side info here,...
(and this is coming from the owner of the Dyno shop, as of last week).
The ONLY aftermarket, full system, out there,....
That is actually TUNED to each bike it was intended for,...
With some actual R&D work,....
Is the Curtis Sparks system.
(that's what he told me,... he's work in the business for over 30 years,... and who am I to argue ???)
He says all the rest are just "bent to fit".

He also said that it dosent mean the others are BAD,....
and he did say, that they all, are an improvement over the stock exhaust.
The difference between ANY of them vs. stock is a great improvement in air flow.
The difference between one vs. the other is negligeable,and
starts to be a matter of splitting hairs.

So what would I do? if I was looking to buy a aftermarket exhaust and didnt want to fork out $300 to $600 bucks for a dang piece of exhaust pipe???

I'd keep an eye on craigslist, and ebay for a decent condition used one. when It got delivered, I'd paint or polish it, order a new quiet core from the manufacturer, Re-pack the muffler,...
and be done with the whole ordeal for hopefully around $150 bucks.

Intake/airfilter ???
K&N, UNI, Twinair,....
Take your pick.
Just be sure that with which ever one you choose,...
You back it up, with a Outerwears prefilter, and you'll be fine.

Next thing to wake up your quad, ...
give it greatly improved throttle responce,...
dosent Compromise any reliability,....
and is very affordable,...

Is the Sparks Timing Advance Key.
WAAAY too much debate to go into here,...
so just go read about it in a write-up I did a while back,
and decide for yourself.....
http://www.exriders.com/vbb/showthread.php?s=&threadid=349499&highlight=sparks+advance+key%2A+guys


The Jury is still out on the 450r carb vs. a properly tuned OEM 400EX carb,...
but I will be doing a Dyno Shootout next week, and will be posting the results.
and once again,.....
for you to make YOUR OWN decisions from.

I hope some of this is helpful information, and you find some benefit and knowledge from it.
Happy Reading,
Happy Riding,

Ride hard, fast, safe, and fun,....
and remember to keep the rubber side down !!!

[TRXRacer1]

Nice write-up. Just wanted to add that the rear shock is agreeably nice but it's wound way too tight! Set the sag on it and then the comp and rebound. You're body will thank you and it's all a free job.

[nevadatrx400ex]

Never gave any thought to a steering stabilizer? shocks I can understand but the 400ex seemed to steer and handle pretty good, are you saying there will be a huge improvement installing one of these? How? wheres a good place to shop for them if I'm convinced they are necessary?

[RIDEREDson]

I don't think its a necessity. Especially for how your riding. I ride MX and I dont even use a stabilizer. Spend the 200-400 dollars else where.

If you're bike feels fine how it is then leave it.

[tri5ron]

Originally posted by RIDEREDson
I don't think its a necessity. Especially for how your riding. I ride MX and I dont even use a stabilizer. Spend the 200-400 dollars else where.

If you're bike feels fine how it is then leave it. How tactically can I put this ?
at the risk of offending somebody, (and my intent is to NOT offend,)...

As I have clearly tried to stress
Consider the sources of all info. , (and opinions), And make your own deductions.
But please read this thread...
http://www.exriders.com/vbb/showthread.php?s=&threadid=349366&highlight=steering+stabilizer

Pay attention to what other Trail Riders, have said in it.

[racerdan24]

Be careful with the synthetic in the 08's...i have read and heard that it is NOT good for the newer quads, especially the 08's and up due to the wet clutch. Use what is recommended in the service manual.....i race and also trail ride mine and use only recommended oil in my 08. Seems to work great and have had no problems.

[IcutMetl]

I was under the impression that most all 'wheelers (including ALL 400ex's) had wet clutches. It is true, you shouldn't use an automobile oriented oil due to the friction modifiers that an auto engine needs, but a 4 cycle motorcycle or atv oil, synthetic or not, will work fine.

[RIDEREDson]

Originally posted by racerdan24
Be careful with the synthetic in the 08's...i have read and heard that it is NOT good for the newer quads, especially the 08's and up due to the wet clutch. Use what is recommended in the service manual.....i race and also trail ride mine and use only recommended oil in my 08. Seems to work great and have had no problems.

I don't understand why not. The motors are the same. The GN4 is good but paying the dealer price will buy get you better oil out there somewhere else.

[nevadatrx400ex]

read alot of good feedback, its really helped. I dont suppose anyone would know or recommend a good beginner quad for my wife, mid 40's, 5'1" 110 lbs, not good with machines, cant drive a clutch in a car, never rode a motorcycle, would need a full automatic, easy to handle.......I've been reading and thinking about a polaris trailboss 330, anyone got a comment if this would be good fit or maybe something else???

[tri5ron]

250EX, but it's just auto clutch, not FULL auto.
(more dependable in my opinion though)

elec. start, driveshaft (practically zero Maintaince ), reverse, and its a Honda.

http://i111.photobucket.com/albums/n148/tri5ron/Fathers%20Day%202009/IMG_9854.jpg

http://i111.photobucket.com/albums/n148/tri5ron/Fathers%20Day%202009/IMG_9885.jpg

my wife LOVES hers !

[nevadatrx400ex]

where did you get the cool rear rack? I could use something like that, saw a website where you bolted a six pack rack out the rear of the quad but yours looks better, did you make it? your quads look good. the 250ex looks good too, didnt know it was shaft drive, but still is smaller and lighter too?

[tri5ron]

Originally posted by nevadatrx400ex
where did you get the cool rear rack? I could use something like that, saw a website where you bolted a six pack rack out the rear of the quad but yours looks better, did you make it? your quads look good. Hahaha ! thanks, some people think the racks on our quads are cool, and some of the younger crowd just cant understand WHY, I would do something like that to a "Sport Quad" LOL !!!
I like to call them our "Crossover" Quads.

mine is now a..... TRX400EX-U Sport/Utili/Trax :D :D :D

the racks are made by Quadboss, and the mounts are brand/model specific.

The Bags are sold on ebay for $69 I belive, they go by a model number of WAB-803, and are exactally the same bag, from the same factory, that builds them for the Tamarac company, and are sold as the 'Tamarac Titan, Cargo Bag, for over $200.

there's been quite a few discussions over it, and I always enjoy it when someone wants to know more about them.
here's a couple threads you might enjoy...

http://www.exriders.com/vbb/showthread.php?s=&threadid=350402&highlight=rear+rack

http://www.exriders.com/vbb/showthread.php?s=&threadid=401034&perpage=13&highlight=pinnacles&pagenumber=3

[nevadatrx400ex]

Hell yea, I dont care what the kids say or think. at my age I want it to be functional. the bag sits back far enough on your 400ex to not be in the way of your normal shifting on the seat trail riding?

[tri5ron]

Here's a bunch more....


http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8845.jpg

http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8420.jpg

http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8261.jpg

http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8260.jpg

http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8203.jpg

http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8210.jpg

http://i111.photobucket.com/albums/n148/tri5ron/03%20400ex/IMG_8204.jpg

http://i111.photobucket.com/albums/n148/tri5ron/Honda%20trx250ex%20quad/IMG_8266.jpg

[tri5ron]

Originally posted by nevadatrx400ex
Hell yea, I dont care what the kids say or think. at my age I want it to be functional. the bag sits back far enough on your 400ex to not be in the way of your normal shifting on the seat trail riding? put it this way,... My son is a Special Needs child. Down syndrome.
So he dosent ride his own quad out beyond our campsite, but that dosent stop us.
Having the rear bag, means we can still ALL go for a family trail ride together. he gets to ride on the back of mine, and he's in the lap of luxury, like he's sitting on the back seat of a offroad Goldwing !!! LOL!!!...

http://i111.photobucket.com/albums/n148/tri5ron/Fathers%20Day%202009/IMG_9877.jpg

http://i111.photobucket.com/albums/n148/tri5ron/Fathers%20Day%202009/IMG_9908.jpg

http://i111.photobucket.com/albums/n148/tri5ron/Fathers%20Day%202009/IMG_9903.jpg

http://i111.photobucket.com/albums/n148/tri5ron/Fathers%20Day%202009/IMG_9909.jpg

[nevadatrx400ex]

Cool, its commendable you go all out to ride as a family. I really dig that rack, will have to look into getting one. Thanks for the nice pics.

[nevadatrx400ex]

Rats!

ordered a rear rack from Quad Boss like you did, well, they discontinued the rack you have and now its a far inferior design where its angled up towards the front and doesnt extend straight across the back like yours does, so, to center my big bag on the rack I'll have to position it considerable further forward over the seat which really sucks.

cant get a refund on the bag, I could get a refund on the rack but dont know if anyone else makes one for this quad???????????

other alternative is to take it to the shop, start cutting, and basically re-fabricate the whole darn rack to make it usable for my needs.

[tri5ron]

the search may be tough, but they can stil be found if you are dillegent and commited. (Read "obcessed" into that, and it's probably more accurate).

occaisionally they do pop up on ebay, so set your favorite search function for "rear atv rack" and get ready to do alot of deleting as they come back with the wrong types that you are looking for.

here are a few possible sources you can try...

http://www.bikez.com/accessories/CMP.htm

http://www.monkeybuttparts.com/pk4/store.pl?sub_section=330

http://www.chaparral-racing.com/Chaparral/search_results.asp?find_spec=rear%20rack&searchtype=AND&mscssid=01259852F0D0481F93465E3EEF66C1EC&Gift=false&GiftID=

http://www.cambridgemetalsandplastics.com/contact_us.html

http://www.candssales.com/store/ATV-Rear-Flat-Racks.html

http://cgi.ebay.com/ebaymotors/Honda-400EX-ATV-Rear-Sport-Rack-Kit-1999-2004_W0QQitemZ330353036437QQcmdZViewItemQQimsxZ200 90818?IMSfp=TL0908181510006r15051

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=140346824326&category=43969&_trksid=p4340.m263&_trkparms=algo%3DSI%26its%3DI%252BC%26itu%3DUCI%26 otn%3D10%26ps%3D63

http://www.bikebandit.com/product/A4502167


I would be happy to take some measurements, and even trace some templates for you of the mounting bracket, if you need me to, so that you could make your own if it came to that.
let me know how I can help.
ron

[tri5ron]

just saw this on ebay. not much time left.
I think I paid $110 for mine. Not including the mounts.
If you get the rack, I'll send you pics/measurements of the mounts. good luck, Ron
http://cgi.ebay.com/ebaymotors/QUADBOSS-UNIVERSAL-ATV-REAR-SPORT-RACK-BLACK-NEW-NR_W0QQcmdZViewItemQQ_trkparmsZalgoQ3dLVIQ26ituQ3d UCIQ26otnQ3d3Q26psQ3d6QQ_trksidZp3286Q2em7QQcatego ryZ43969QQihZ008QQitemZ180411695340