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What to do to make my XR400 start easier

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I have an 04 XR4 that is a bitch to start. I run 98 octane fuel, have just changed the plug. set idle amd mixture on the carbie as per manual and even done valve clearances. Basically the only thing I havent done is changed jetting. I run standard jetting for sea level according to my local dealer. Would changing the jetting help it starting and if so what size is recommended?:)

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The stock jetting is too restrictive... Do the "Gordon's Mod's" (Sticky at the top of this forum) This will make a "HUGE" difference in how it starts and performs! :)

All this extra performance for a very low cost.

Perc

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I've had an 01 400 and now an 04...I've found that with the right technique, can be started easier than normal.

I hold the decomp. in and kick over a few times; 4-6. Then I find the sweet spot with the kicker (i've let go of the decomp) which is when you can tell there is some resistance; on mine it's only about a 1/4 way up from the bottom of the kick. The sweet spot can also seem to be a little higher, but try staying lower.

Anyway, mine won't start on the first kick but usually the 2nd or 3rd.

Of course choke all the way on and I work the throttle (a smooth twist into full throttle) during the kick.

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The hard starting reputation of XR4's is a result of rider failure, not the bike/carb. Usually the problem is too lean a pilot jet and moving the throttle when kicking. Correct jetting for alt and temps will deliver quick starts hot or cold, and the carb is very tolerant of wide swings of temp and alt.. Many mistakenly think the Mikuni pumper is the answer, failing to realize that the "correct" jetting already installed in the Mik is the reason it starts better. I have owned three XR4's and never seen the need for anything more than proper jets from the Texas coast to CO. $10 and fifteen minutes is all you need.

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I just had my bike tuned and carb cleaned. It was from one of the oldest shops in the area. I asked him to check the jet and get another one if it was wrong size. He said it was okay. It still hard to start, though I will take a lot of the blame. i have had other dirtbikes but they were two strokes. I think the technique my be a little different.

PO had removed the snorkel. I was told the bike was from California but it looks to have spent more time in Wa. I live in Oregon so the jetting should be okay. Once it's running it works great. No flat spots, backfires or hiccups. (For sale by the way).

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The first thing I would do is to bump up the pilot jet one size. Often, that will ease the starting problems. Here is the US, they come lean.

That is a $4.00 easy fix.

The pumper is the ultimate fix but will cost you at least a couple hundred.

Many mistakenly think the Mikuni pumper is the answer, failing to realize that the "correct" jetting already installed in the Mik is the reason it starts better. I have owned three XR4's and never seen the need for anything more than proper jets from the Texas coast to CO.

If the non-pumpers are so good, why do all the new 4-strokes use pumpers ?

The stock XR400 carb jetted properly is OK. It is by no means good or great.

It is not all about 1-2 kicks as apposed to 5-6 kicks or even 15-20 kicks. I would take the pumper performance and 8 kicks to start over the stocker performance and 3 kicks to start.

The difference in performance is like riding a 250 vs a 400.

Anyone who tells you that a stock carb jetted right is as good as a pumper has never ridden with a pumper for any length of time.

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Mine was the same even after the Gordon mods.

Try turning the idle speed up 1-2 turns and using the 3-4 slow

kicks with full choke before kicking fully.

After it starts then turn the idle speed down to normal.

I always wondered why Honda would put this so easy to adjust

idle speed adjuster on their basic 4 strokes?

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I havent heard anyone mention valves yet. If they are a little on the tight side the bike will start hard. More so when its up to temp, but my 97 is a 1 to 2 kick starter. I have the stock carb, and yes the pilots are a problem especially if you leave any of this ethanol (junk a$$) gas in it for any length of time. Also just saying I think the 98 octane is a waste when good 93 will do fine. Where are you getting 98 octane from?

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I havent heard anyone mention valves yet. If they are a little on the tight side the bike will start hard. More so when its up to temp, but my 97 is a 1 to 2 kick starter. I have the stock carb, and yes the pilots are a problem especially if you leave any of this ethanol (junk a$$) gas in it for any length of time. Also just saying I think the 98 octane is a waste when good 93 will do fine. Where are you getting 98 octane from?

Whats up jcat! Headin to Cedar Creek next weekend if your interested buddy. Let me know. :)

I think what they call 98 in Aus is = to our 93. Just a different octane rating system.

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I have an 04 XR4 that is a bitch to start. I run 98 octane fuel, have just changed the plug. set idle amd mixture on the carbie as per manual and even done valve clearances. Basically the only thing I havent done is changed jetting. I run standard jetting for sea level according to my local dealer. Would changing the jetting help it starting and if so what size is recommended?:)

what jetting are you running. My xr4 (01) wouldn't start well till I rejetted up from stock. I bought the next three sizes up for both the pilot and the main and tuned it myself. Started 2 to 3 kicks always after that, even with ice on the seat. No matter how well I tuned it the off idle bog would not go away so I installed a Mikuni pumper from xr's only in L.A. Best 400 dollars I have ever spent on a bike. Do a search on how to start the xr4 here, there is a lot of excellent info about how to use the decomp lever and why and to stay off the throttle and why

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98octane is available at most service(gas) stations here in Australia

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Once the bike ishas been started and warmed up it starts first kick nearly every time its just initial start up

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Sorry Rayza, I didnt see you were from down under. I usually post after work to wind down so sometimes tired. If it only starts hard cold then check to see if your pilot is clean. I am not as familiar with 04s but a plugged pilot will make a bike cold blooded. If it still starts hard then try richening your fuel screw a quarter turn(out) and then see if it makes a difference. Heck ya Michigan 400 I am ready to ride. PM me on the day. Cedar creek sounds good. :):)

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Never touch the throttle during starting. Worst thing you can do.

That is if you have a pumper carb.

As when my bike was stock, you had to give it throttle to start. And, when cold you had to keep on the throttle to idle until it was warm. Once warm was one kick and would idle w/o any help

I just put on the pumper, starts first kick and will idle...plus the low to mid range response is unbelieveable!

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i'm with seehogs, full choke no throttle kick it over quickly (doesnt have to be slow) a few times to get the fuel in (the decomp will have kicked in and theres not much compression). Then stop, put to top dead centre (feeling the compression), then kick (almost starts first time every time)

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OK gents solved my problem. instead of believing the honda bike shop advice i pulled the bowl of the carby and rejetted from a 55 pilot to a 60 pilot. Also put in a 162 main tweaked the idle just a bit and now it starts much easier. been able to get it first kick twice from 2 cold starts. (kick through 3 - 4 times then find TDC centre push through to first bump and then wham big kick and it starts. hhhaaaapppppeeee

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