1000 to 3000 revs running crap

Fastman · Post by **Fastman** » Tue Jun 15, 2004 3:59 pm

Just got a %%WORD2%00 exup, don't know much about it. but it runs really crap from just above tick over to about 3000 to 3500, when it picks up and goes, starts first touch ticks over smooth, but just runs really rough at the low end,exup valve is moving ok. i think it is running too rich, as it sometimes sounds like it is hunting a little. Any idea's<img src=http://www.ezboard.com/images/emoticons/frown.gif ALT=":(">

dragracer1951 · Post by **dragracer1951** » Tue Jun 15, 2004 5:50 pm

Clean the carbs...it's dirty in the idle circuit Might be a little rich at the pilor air screws Have a jet kit???? if not then it's dirty Jim

Post by **FZRDude** » Tue Jun 15, 2004 11:36 pm

What is this Jim? No big bore recomendations? <img src=http://www.ezboard.com/images/emoticons/roll.gif ALT=":rollin"> Tim <img src="http://img69.photobucket.com/albums/v20 ...  Dir. of Entertainment<a href="http://eddieandthecruisersmc.com" target="top"> Eddie & the Cruisers</a>

Nbot · Post by **Nbot** » Wed Jun 16, 2004 12:39 am

see lots of guys with same probs in 89/95 fzr1000 section..."0-3000 stumble/flatspot" and also "rev problems"....appears to be common, check the links provided......

flyingcircus68 · Post by **flyingcircus68** » Wed Jun 16, 2004 5:15 am

A big bore kit, frame polishing and a fancy paint job should help.<img src=http://www.ezboard.com/images/emoticons/nerd.gif ALT="8o">

dragracer1951 · Post by **dragracer1951** » Wed Jun 16, 2004 6:20 am

<img src=http://www.ezboard.com/images/emoticons/laugh.gif ALT=":lol"> JYa know Tim....If I didn't know any better I'd swear you've been talkin to folks that know me!!!!! <img src=http://www.ezboard.com/images/emoticons/laugh.gif ALT=":lol"> <img src=http://www.ezboard.com/images/emoticons/laugh.gif ALT=":lol">

dragracer1951 · Post by **dragracer1951** » Wed Jun 16, 2004 6:26 am

The stumble and rev problems are usually confined to the people (my self included cause I didn't know any better<img src=http://www.ezboard.com/images/emoticons/eek.gif ALT=":eek"> ) that have a Dyno Jet kit as they run very rich at the recomended settings. That and the fact that these bikes are getting old (What the hell...so am I!!) and the emulsion tubes are wearing out and they are being bought by nice folks that may not have the technical skills to maintain them properly, so the carbs fall into disrepair and are dirty... But mostly it's the Freekin jet kits And don't even get me started on pod filters Jim

Fastman · Post by **Fastman** » Wed Jun 16, 2004 4:17 pm

Hi thanks for all your comments. It may be an old biekto you lot, but i have been rebuilding and tuning the suzuki GT750 two stroke for years, this bike just seems so modern, it's me, i am from a different era. ha ha. Seem's that the needle jets don't last too long in this bike, and mine has done 31,000 miles, and don't look to have been changed, new ones just been ordered.

Nbot · Post by **Nbot** » Wed Jun 16, 2004 9:41 pm

Pretty nice to have this forum I admit.....

Thermicman · Post by **Thermicman** » Thu Jun 17, 2004 3:57 am

Hi Fastman, I know this is a little bit different from the other replies to this thread who all seem to mention carbs but I experienced the same thing on my '89 EXUP. It used to get really rough and then would eventually run on just three cylinders. When I bought new plugs - hey presto, it worked OK....for a while until the same old problems reappeared. This cycle repeated itself 3 times. To cut a long story short, I eventually decided to replace the HT leads having checked the carbs, EXUP valve, coils, etc according to the Yamaha manual specs. I bought some lovely new NGK racing leads (sexy red colour) complete with straight suppressor caps, coupled these with those mega pricey iridium spark plugs and Bob's your dad's brother - no more problems and the bikes been perfectly behaved now for 2,000 miles. It revs nice and crisply and pulls out of 90° intersection bends in 2nd gear where the revs may drop to 1200 - 1500 lovely and sweetly. It might be worth a try! Good luck!

Fastman · Post by **Fastman** » Thu Jun 17, 2004 11:43 am

Good move, that will be the next step, striped the carbs today, sure enough the needle jets are shot, nice and egg shaped. So the leads are intererchangeable?, not really looked but i presumed they would be of the sealed into the coil variety. You can change them then?

Thermicman · Post by **Thermicman** » Fri Jun 18, 2004 3:58 am

Hi Fastman, In answer to your queries, the new NGKs come complete with straight HT caps which fit onto the EXUP's plugs no problem - you don't need to get angled HT caps. Also, the new NGK leads are all just a bit longer than the longest OEM lead that the EXUP uses (phew!!). I bought four and then trimmed the lengths to match the OEM lead lengths. The best way to do this is to fit the leads to the plugs first and then see how much length you need to get to each coil - allowing a couple of centimeters for f*#k ups!! Don't forget to make a note of the firing order and which lead goes into which HT coil entry!! When you come to fit the new HT lead ends into the HT coils, the best thing is to remove the coils completely from the bike and just twist and pull out the old leads - they are not sealed into the coils, not on an '89 EXUP, anyway. I then put a tiny smear of washing-up liquid onto the silicone outer and then pushed the lead into the coil entry. The fit is "snug"! Measure with a small screwdriver or something, the length that you have to insert the lead into the coil entry and then put a felt-tip pen mark onto the new lead the same distance from the lead end. This will let you know how far you have to fully insert the new lead. When you've got it in as far as it will go (Oooh errrr, missus!!), you then have to twist the lead around and around as you push it in the remainder of the way. This is because there is a threaded spike right down inside the coil entry hole that makes for a good connection with the HT lead. PS. While you're screwing, don't forget to disconnect the lead from the plug or you'll twist the lead to bits!! I have probably made this sound more complicated than it really is! Sorry! It shouldn't take you more than a couple of hours to do the job properly including removing the tank, etc. Good Luck!! <img src=http://www.ezboard.com/images/emoticons/wink.gif ALT=";)">

EXUP Worldwide

1000 to 3000 revs running crap

1000 to 3000 revs running crap

Been there...done that....

Re: Been there...done that....

ditto........

Re: ditto........

Big Bore

stumble

stumble

ditto....

Running Rough

Hi Thermicman

rough running EXUP