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Discussion Starter · #1 · (Edited)
Hello, this is my first post on this site, but looking at other threads, you guys have helped me out alot, so once more? :lol:

I bought a 1988 Mojave in really rough shape not running, bought a new carb because the old one was leaking gas into the motor and pressurizing the crankcase. The new carb solved that problem out very well...It has also had alot of motor work from the previous owner (bored out, bigger carb, bigger cams, valves, K&N instead of airbox, and new muffler)

But, now I am having some other troubles. First off, when I go to start it, it won't start at all without starting fluid, even if it has ran and sat for more than 10 minutes. Even with the starting fluid, starting is still difficult (10-15 kicks).

Also, when it is running, it has to warm up for about 10 minutes before you can even ride it, or it will bog and stall with half throttle. When it is warm and you are riding it, if you try to give it WOT, it will stall out, almost as if it is not getting enough gas. I tried almost everything I can think of to get this resolved, cleaning the carb several times, putting a in line fuel filter, and practically adjusting the jet every which way, but still same problem. Any ideas??:confused::confused:

Also forgot to mention, that the choke cable on the new carb was rusted, so I cut it down to where it wasn't and it works fine now, but isn't connected to the handle bar like it should be. Even witht the choke on, starting it is difficult, and it seems that once you pull the choke while its running, it smooths out and sounds strong. But even with the mixture being richer, it still runs better with the choke on.

Thanks guys.
 

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First do a compression test and then check the valve lash. Mojo have always had head issues with the seat sucking into the head and then the valves can't open. If it takes a long time cranking to start then it's possible you have valve clearance's out of spec. Start with that and let us know. I have an 87 parts mojo so if you need something let me or post it alot of guys have parted mojos on here lol.
 

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Ususally it should be .007 or.008 is were it runs its best from what ive tested and seen on other ones. If anything runs better with choke on, it isnt getting enough gas. I had a quad a while ago were it would run fine but wouldnt start up without starting fluid either. No matter if it was hot after a ride or cold. The problem ended up being the carb boot was bad and had a hole in it. Also, if it is bored out with alot of modding work done and a pipe, a stock carb with stock jets will make it run like crap. Did you put the old jets in the new carb? Probably not the best idea if it was leaking but just to see if it would run any better. Or Getting maybe a jet kit. Hope this helps. Also like spdrcr i also have a parts mojo. Like he said, alot of people have parts lol.

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Discussion Starter · #6 ·
The old carb was a bigger carb, the jets would probably not fit. But it seems to run better on the leaner side when adjusting the jet screw. Do you happen to know where I can find bigger jets for it?
 

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Sure. Any racing store or ebay. Were are you located? I may be able to find a couple places. Do you know what kind of carb it was? Maybe you can just get a rebuild kit for it. When it leaks that bad, the little o ring in were the needle float goes and stops the gas doesnt seal correctly so it leaks, or possibly a stuck float. When you say leaner side? Do you mean more in on that jet or more out? With those type of mods, it should be about 2.25-2.50 turns out from what ive read. Ebay you can scoop up a jet kit id reccomend the sigma because it seems to be the best. Or as i said a local kawasaki shop or racing store. Hard starting though would most likely be valves or timing. Have you checked your valves? If you do, check the tension on the timing chain. How does the sparkplug look? Hope this helps.

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Discussion Starter · #8 ·
Yes it does help, you've been the most helpful poster haha. I'm not sure the kind of carb it was, it honestly looked very hodge-podged together. I can take a picture of it tomorrow and maybe you can tell me? I'm honestly not %100 sure it was leaking gas into the motor, it was what I was told from asking around on other sites, but when it did have the other carb on there, it would run WOT all the time and pump oil from the crankcase vent. The oil smelled like it had gas in it, and when I took a blow torch to it, it was extremely flamable (more so than regular oil). When I say leaner side, I mean I was screwing the jet screw in, that is leaner right? I'm not even sure that getting a rebuild for that carb would be worth it, but would the mojave even handle a bigger carb, or is this the result of a little too much modding? I would think that maybe if fuel is an issue, that the jets on the stock carb would be a better way to go? Now that I was looking Jets up on Ebay, it occured to me that it did seem that it was running kind of on the hot side, which to me seems like it would be running too lean, and it does pop a little which was another sign...but richening it causes another problem, it will bog out and give me like no power at all. My ZIP code is 18301 if that helps you at all, there is Hellbound racing nearby but I'm not sure if they would have jets.

Sorry for the lengthy posts
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Correct. In is more air(leaner), and out is more gas(richer). Hotter would be leaner. I remember another Mojave i had that would run great, strong, fire first kick, and when it got hot, it ran like crap. So for 4-5 minutes it runs good and then it runs bad. Does your quad run good when its cold? I bought a 14 dollar rebuild kit and that solved my problem. I would probably buy a couple of main jets and try them all. I would definitely not go back to the old carb, its probably not even for a Mojave but people just throw whatever in there because it fits. Unfortunately, i forgot the size of the stock main jet lol. I want to say the stock is either a 25 or a 30 but im not positive. It is possible to handle a bigger carb, they do have a couple of them out there but i say its honestly better to mod your stock carb then spend another 250-300 bucks maybe more on a bigger carb. Generally, if a machine runs better with the choke on, it is running too lean. Also, with a modified intake to let in more air, and a modified exhaust providing better flow, and a bigger piston, needing more gas, more gas needs to get in the engine. I believe a bigger main will solve the running poorly problem, not knocking your machine. But before spending money on anything, it wouldnt hurt to adjust the valves. Or atleast see if there in spec. Sorry for my lengthy response as well. Also, Greg over at cycle works racing is an expert in the mojave and can also help you with any questions you have as well if you cant get the help you need on the forum, he also has a bunch of kits/parts. His number is 717 359 5060

Thanks
 
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