Mid and High Rpm power loss and bogging

[newyorkrider]

Hey everyone. I just had a couple of questions about the carbs on the 454. So i bought a 454 that had been crashed and tied to a pole for about 5 years. It was pretty cheap and was half bobbed so i just took it on as a project. The guy said it wasn't running but i started it up and rode it about 100 miles back. it was alright but i couldn't really analyze it because of all the faulty things. The tank was rusted all over inside and all the fluids had water in them. I changed all the fluids, the spark plugs and the battery. I went out for a test ride and first thing i noticed was that the bike would kind of go crazy past 1/4 throttle. It felt like i was opening and closing the throttle really fast. The only way to get over that was to keep shifting up the problem is im already in 6th gear every city block while my dad barely gets to 3rd on his bike. Then i took it to a highway and that was a really bad idea. I had the worst time keeping up with my dad on a xr400. I was in sixth gear and it just couldnt pull anymore. when id crack open the throttle it would just bog and slow down. I had to pull in the clutch to let the rpms rise and then dump it. Eventually i got home to fix it up. I took the bowls of and they were alright a little bit dirty and some sort of red dust but for the most part it was alright. i tries to take the top off and take the diaphragms out for inspection but they were pretty much seized on so i shot carb cleaner through every line until it stopped coming out brown. Then closed it back up and went for another ride. The fist thing i noticed was that it backfired alot now but ran a little bit better. i still get random surges if i open up the throttle past a 1/4 turn. As for mods it already came with pod filters and the crankcase has like a line running down past the engine so i guess its an overflow and theres another filter on a long hose that runs to the top of the engine. It also had the mufflers removed. Any ideas on whats going on? An i guess ill ask these questions here instead of making a new thread. 1. Does the electric starter normally turn so slowly on these bikes? Its when i hit the starter in barley moves until it randomly starts. 2. On the head tube of the frame it specifies that the bike is a 454 but the engine has 450 at the beginning of the serial number stamped on it. Does this mean that its a 454 frame with a 450 engine or is that just how they're numbered? and finally 3. The clutch has very little range as to when it engages. i have a decent amount of play in the lever but its almost as if the cable is to tight. It engages about a centimeter or less before completely letting it out. Well thats it. Thanks in advance guys. 

[eaglerider]

You have a ways to go....Rather than give it all to you in a lump, we will take things in steps. First, something has to be done with the rusty tank, with a rusty tank, u will continue to have fuel/carb problems. U need to clean and seal the tank...there is a "kit" available for that, available from most motorcycle shops, just follow the directions. The jets and orfices in the carbs are very likely partially clogged up, preventing proper fuel flow, so it is recommended that the carbs are removed (do not separate them) and cleaned thoroughly. These engines "like" a good valve adjustment about every 5,000 miles, and since you have no idea when or if it was ever done, this needs to be done...adjust the valves using the higher values given for adjustment. Valve adjustment effects very severely, the running and acceleration of the bike. The hose that u spoke of is a crankcase vent, and should have a filter on it...if u go to the Photo Galley and look thru it, u will find pics of the filter that most all use..it is available from most auto supply stores. The clutch cable should be adjusted per the instructions in the manual. We do have an on-line manual available to read and refer to. Download our 454 toolbar, and navigation thru all our "features", including the manual is there. However, we do recommend that you obtain your own "hard copy" manual. After you have taken care of all these things, the bike should run much better, and we can move on from there. Welcome to our family....ask questions when in doubt....that's why we are here.

[Blaine]

Welcome to the family.Eagle answered all that you need to do first.454 or En450 is the model.450cc is the size of the engine.As Eagle stated,do some studying & than we can go from there.

[newyorkrider]

Thanks a lot for all the info. I forgot to mention that i cleaned out the tank and now its clean as a whistle. I also installed an inline fuel filter and have not noticed any debris or rust caught in it. Im definitely going do a valve adjustment sometime soon hopefully tomorrow. Thanks again for all the help.

[newyorkrider]

Thanks for the welcoming, fellas. By the way heres a quick shot of it.

[Blaine]

Jun 11, 2013 18:31:01 GMT -6 newyorkrider said:

Thanks a lot for all the info. I forgot to mention that i cleaned out the tank and now its clean as a whistle. I also installed an inline fuel filter and have not noticed any debris or rust caught in it. Im definitely going do a valve adjustment sometime soon hopefully tomorrow. Thanks again for all the help.

Just take your time doing the valve adjustment & you will be fine.Just be careful when removing the valve cover not to drop the tach drive or locating dowels.A small piece of vacuum tubing over the tip of the tach drive will keep it from dropping on you.The locator dowels can be guled into the head once you have the valve cover removed so you don't need to worry about them in the future.After your valve adjustment if she still bogs then we will tackle that problem.

[newyorkrider]

Well heres a update. I havent been able to do a valve adjustment because its been raining alot lately. It wasn't supposed to rain until later today and I didn't want to get caught in the rain with the motor open so i decided to take the bike for a spin. I decided to covered up the pods with socks to restrict airflow and ohh boy that did the trick. it started right up instantly with out me cranking on the throttle and it had power throughout the whole rpm range. All the problems were pretty much solved until i ended up dumping it on an oily street. well until a clutch lever and shift lever come in ill have time to do a valve adjustment. 

[BenInPA]

Maybe Blaine will chime in with more detail on this. There is air restriction needed on the pod mod. Using an aluminum soda can cut and slid inside the pod to restrict the air flow. I think there is a thread under carburetor that talks about using the soda can.

Sent from my Droid 4 using Proboards Mobile App. ;D

[Blaine]

If you cut 3 coils off the top of the diaphram spring you can run unrestricted.A weaker spring means the slide will respond quicker with no bogging & you have quicker response.I started out with the soda can restriction & found this by trial & error.

[newyorkrider]

well the bike was running awesome ever since i did the carb mods and removed the reed valve emissions thing because it was just shooting oil out the filter that was there with the pod conversion. Well heres the new problem. decided to do a speed run and the bike was goin great it got up past 95ish if not more. ran like a beast and had no complaints. I ride around for another 20 minutes and then when i get into some traffic i notice that the idle just shot up ridiculously high. i dont have a tach but id guess i usually idle at around 1000 to 1200 rpm but this time it went up to around 4500-5000. It was ridiculous. i couldnt pull the clutch in or it would sky rocket. i had to be in gear and drag the brakes to keep the rpms low. anyway i finally get to a place i could stop and shut it off. i let it cool off incase it was an over heat thing. i start it back up and it shoots up. i back off the idle screw over a full turn and that settled it for a while. then i get back on the highway and i lost all my top end power. barely pulling past traffic. if i go WOT the bike literally goes silent and makes a raspy sound and as soon as i let off the throttle it revs up real high for a second. any ideas fellas?

[Blaine]

Sounds like you may have torn a Diaphram rubber or one of the slides are hung up (sticking) remove your filters & raise the slide with your fingers you should hear air & the slide should shut immediately.

[newyorkrider]

Jul 16, 2013 21:19:57 GMT -6 Blaine said:

Sounds like you may have torn a Diaphram rubber or one of the slides are hung up (sticking) remove your filters & raise the slide with your fingers you should hear air & the slide should shut immediately.

I checked both of them out and they seem fine. both go up with a bit of resistance but come right down.

[gonzo]

My bike did the same high rev problem too. As suggested here I shut off the fuel line, emptyed the carbs by the drain plug. Got a huge syringe (1" by 5") put a vaccum line on it and filled the carbs with liquid seafoam till it ran out the over flow (do you have a vaccum line on the overflow tube for the carbs running to the bottom of the bike) Then let it sit for 3 days.
My bike wouldn't start after I drained it so I pulled the plugs to let the cylinder air out. Instant difference, now my bike idles, though it's a 900 rpm idle when cold then goes to 1200 when warm. So I guess try liquid seafoam!

[lamestlame]

It may be the second vacum line if it isn't closed off it will cause the rise in rpms check to make sure the carbs are all fastened well you can use some starte fluid on the fittings to see if this is where the air is going in.