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  Topic Review (Newest First)
05-16-2019 08:50 AM
Stevo2vabch Ohh and any recommendation how to clean the tank? As dirty as this carb is I definitely want to try and clean the tank but wasn’t sure what else I could do besides put gas in it, shake it, empty it and then repeat a few times.
05-16-2019 08:49 AM
hoser Honestly, that carb is so scuzzy that I wouldn’t run it without a serious cleaning. I know you said you are using carb cleaner, but it needs more than that. I would go down to your local Napa and get a gallon bucket of carb cleaner, it’s different than the stuff you spray. It comes with a basket that you can put the carb in and dip the whole thing. You do have to remove ALL rubber and plastics pieces from the carb, but the stuff works well and cleans where you can’t see or get to. I would dip that carb for at least a day. Any little flake of that crud in the bowl could lodge into a jet or orifice and make it run bad intermittently, it’s worth it to just clean it properly now that you have it off and apart.

The slide and float can be sprayed with brake cleaner, but just be careful to not saturate any plastic or rubber with the spray type carb cleaner for too long and soften the material.
05-16-2019 08:36 AM
Stevo2vabch Thank you Hawk-Trx. I ordered quite a few sized jets. As far the TPS sensor, I don’t think there is a plug for it on my wiring harness. Guy I purchased it from said that the harness was race cut. So I’m pretty sure that he only left what was essential. Thank you for your offer though.
I started disassembling the carb further last night. Is there anywhere in the carb that I should not be cleaning with carb cleaner?
I did purchase a rebuild kit from All Balls. I also purchased what was called the mid-body gasket kit. Ohh and also a new diaphragm. I just don’t want to accidentally mess something up that I didn’t purchase. For instance the slide plate and the floats. Can they be cleaned with carb cleaner or will it ruin them?
05-15-2019 02:51 AM
hawk-trx No need to replace any brass as long as they are the right side, 180-185 is pretty close 160 is way to small. Stock is 118 but the hrc kit bumps to 185 and it has been close for me in the past.

Carb does look like new gaskets and o ring would be a good idea. Try jets r us or sudco. Also it wouldn't hurt to try racers edge jonh stocks lots of stuff for fcr carbs but might have some stuff for these.

It's been a long time sence I worked on one of these carbs but it looks like someone cut the TPS wires, never understood why people do it but some do. It should run fine with them cut. I will check and see if I have a couple of these carbs, if I do and you want the TPS I'll send you one.
05-13-2019 11:40 PM
Stevo2vabch Ok, so I got the carb off. Here are some photos. I only got the bottom bowl off at this point but I didn’t notice a couple of things. There is a plug for a sensor that is not plugged into anything. (On the carb) Also there are set of wires up at the top of the carb that are cut.
The R&D a/f adjuster has a black rubber coating that is kinda ruined from the fuel leaking onto it. But the jet end of it that screws into the carb looks kinda like it is kinda dirty. (See photos)

As far as the pilot jet, do you recommend replacing it? Or should I just purchase a rebuild kit? If so do you know where you can purchase a OEM rebuild kit? All I can find on the internet is aftermarket kits. The main jet I could not make out if it was a 180 or 160.
05-12-2019 06:39 PM
hawk-trx Check the pilot jet
05-12-2019 03:34 PM
Stevo2vabch Thank you all for your comments and help.
I think that I got the leak thing on the carb figured out. There was no clamp on the inlet hose of the carb. See the attached photo.
But now I am running into another issue. It’s taking about 10 kicks to get it started when the motor is cold. Then when you take it off of choke it doesn’t want to stay idling. If I give it some gas right before it’s about to stall out it will stay running but as it will kinda pop and puff a little bit as the isle goes back down. Think that it’s maybe too lean?
05-11-2019 02:06 PM
Originally Posted by hawk-trx View Post
Question to hoser on the fuel leak, I have had fuel screws back out and not leak, I was under the impression that the o ring was for an air tight seal no a fuel seal, am I mistaken?
So Iíve been messing around with some different carbs this morning and I have an answer for you! I donít know!! Lol! I always thought it would leak because it meters fuel, but it seems fuel is only metered when under vacuum, so when running it pulls the fuel through and when not running it doesnít, so it maybe wouldnít leak??? I dunno, I am by NO MEANS a carb expert, I rebuild maybe a dozen various carbs a year, so I could be completely wrong.
05-11-2019 12:39 PM
hawk-trx I liked Sunoco 110 for no other reasons then the smell,availability and cost. I had an issue with vpC12 and U4 leaving crystals in the exhaust ports when it was stored in the winter. 99% of what I used was pump fuel mixed with kemco octane supreme. It is a real booster that works in full points not 1/10ths tested it on the dyno and made the same power as Sunoco and C12 fo about half the cost. It is still available from wild bills corvette but he has doubled the cost, now I use Torco accelerator which also boosts to 105 octane. Unfortunately it does not have
Tyrethelne lead as a boosting agent. For me it's much easier to use have this on hand then 5gallons of race gas
05-11-2019 09:27 AM
Stevo2vabch Hawk-Trx - Thanks again for your reply and help. Do you have a preference for race gas? I used Cam2 in my previous quad a few years back and really liked it. I was running 110. This guy said he was running VP C16 in this one. I plan on pulling the carb off this weekend to confirm that is exactly where it’s leaking from.
05-10-2019 09:56 PM
hawk-trx The only time changing fuel has ever required a jet change for me was with oxygenated fuel, c12, 110, and kemco with 91 pump mixe to 105 are the only fuels I have ever tested on the dyno (and U4 the oxy fuel) my AF readings were all almost identical as were hp readings.

I have found a oring at autozone before, it's not in their normal o ring box but one for fuel/carbs, but make sure you have the washer too and it wasn't lost when the RnD screw was installed.

The best temp gauge I have seen is the ESR

Didn't mean to answer for anyone else just trying to save you some time
05-10-2019 08:15 PM
Stevo2vabch Thanks everyone for your comments and help.

Thrown Stones - I will check into one of those temperature gauges. Any recommendations on brand?

Hoser - Thanks for your help. Do you know if I can you go to a hardware store and match the o-ring up or do you need to order it from Honda? Or does this o-ring and washer not come from Honda and you have to get it from R&D?

Hawk Trx - If I drop the octane to 110 will I really need change/tune much? Also what kind of coolant are you running in yours?

Another thing I did confirm is that this quad has a crf450 flywheel, stator, ignition and cam in it. The carb is from an 06 plus trx450r. Anyone have any experience with running this set up? I can tell you that the thing revs quick and when you punch the throttle it hits hard. I’ve been riding since I was 5 and I am now 36. So when I say this thing rips I’m not some newbie that just started riding or just upgraded to a 450 that’s like “Omg this thing is so fast”.
05-09-2019 08:56 PM
hawk-trx Agree with the guys above, nice quad, 116 is overkill, rd air screw and an idle adjust screw, dropping to 100-110 octane won't require Rejetting

I know nothing about Gibson arms, most use the same joints like houser, JD, lonestar but those look different

Question to hoser on the fuel leak, I have had fuel screws back out and not leak, I was under the impression that the o ring was for an air tight seal no a fuel seal, am I mistaken?

As for the radiator, I have a fulidyne, and a pwr (the ones mishimoto copied) and they hold very little extra fluid (like 4oz more) but neither of my fans come on and by removing the fan it should increase airflow slightly. I also run ESR inline temp gauges and mine don't run over 210 and that's after repeated drag passes.
I will add the instructions from one on my radiators included how to reinstall the fan, but if your harness is race cut you may have to wire from scratch
05-09-2019 12:54 PM
hoser I agree, nice looking quad.

The screw that’s leaking was called an air fuel screw, but it’s actually a fuel screw. They are very nice for easy carb adjustment, but it sounds like maybe the o-ring that goes in there under the spring and washer was left out and that’s why it’s leaking fuel, might be worth checking out. You can read about how to tune your carb with that fuel screw by reading the jetting sticky that is at the top of the engine forum where you posted this thread.

I also agree that you don’t need to be running 116 octane, and you could safely drop the octane level and not have to worry about rejetting it.

Some guys remove the fan if they are always moving or racing and get good airflow over the radiator at all times. If you let the machine idle or are doing slower trail rides you might want to consider throwing a fan back in there.
05-09-2019 11:41 AM
Thrown Stones Good job on the find. That looks like a nice ride. Mishimoto radiators have a larger capacity. That's probably why there is no fan. Get an in-line coolant, temp gauge. That's a good way to monitor the temps. If your compression is around that 13.5, the 116 octane is overkill. Good luck and enjoy.
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