Some carb questions

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valleyguy
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Some carb questions

Post by valleyguy »

Okay got my new to me 90 kdx 200 home lastnight and it was 11:00 by the time I got it unloaded so I just parked it in the garage. Today changed the tranny fluid, fresh gas (32:1) and a fresh plug. Took me a few kicks before I relized the choke was not on then it fired right up, drove it around the yard a bit. first thing I noticed was that the idle was really low, easy fix but I didn't do it yet, second thing was that it seemed to have a bit of a bog when you get after it and seems slugish through the entire rev. So I read the carb tunning stuff on the site and figure I'll give it a go. Now my main problem is that the engine was just rebuilt and he didn't know what size the rebore was and he said he took the jets and drilled them out so I have no idea where to start with this thing. Do I buy stock jets try them and then tune from there? Also do I have to remove the carb for every jet change?
Last edited by valleyguy on 10:45 am Jul 17 2012, edited 1 time in total.
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Julien D
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Some cab questions

Post by Julien D »

Drilled out the jets? That doesn't add up. The stock jets are too large as is. I'd order some jets from jets r us, sudco, or psep.biz and start jetting. 155/45 is a good starting point for most people, but your current elevation would help. The E series can't be bored too far, so I don't think bore size will be much of a concern. Being that you just picked it up, might be worth tearing down the top end to figure out what's in it, if it's been sleeved, and the condition of the KIPS valves. The subvalves are problematic on the E bikes.
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valleyguy
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Re: Some cab questions

Post by valleyguy »

I'm in nova scotia and the elevation here is 92 ft above it's the first rebuild on the bike (previous owner didn't ride it much) I asked him what size the jets where in it cause he said it needed to be tuned because of the rebuild so he said he opened them up a bit with a drill bit| ( beats me I was confused as well) kips are great motor was toatally dissasembled and cleaned and put back together. It doesn't seem to run to bad I only got to run around in first gear till I get my plate for it so I can take it off my property. When free reving in nutraul it would bog real bad but seemed better with a load on it. I guess I'll order some jets and try it myself. only thing changed on the bike is an fmf gold series front pipe and a fmf power core muffler.
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Julien D
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Re: Some carb questions

Post by Julien D »

I see. Do you know if this is the SR model or not?
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valleyguy
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Re: Some carb questions

Post by valleyguy »

I would say it is not, not even a speedo or anything just a headlight and tail light. I just got it legal to drive off road so I'm gonna take it for a better ride tonight and see how it acts.
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Julien D
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Some carb questions

Post by Julien D »

Right on. Does it have a steel fuel tank, or an oil injection pump? That would be a dead giveaway for the SR model.
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valleyguy
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Re: Some carb questions

Post by valleyguy »

Nope, all plastic.
valleyguy
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Re: Some carb questions

Post by valleyguy »

Ok had it out for a ride, seems low on power for one but if you rev it quick out of gear it rev fine but if you try to give it a good goose and hold it there it bogs down until you let off. Now put it in gear and go, it's not bad just cruising but anything over half throttle it wont rev up anymore. From a dead stop getting after it it won't even spin the tire it just slowly gets up to speed, it seems like at a certain rpm it wants to haul ass but then it just falls on its face. Oh and it wont stay running at an idle. So anyideas where I should start?
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scheckaet
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Some carb questions

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valleyguy
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Re: Some carb questions

Post by valleyguy »

I did check that out prior to this post but i was just looking for a general direction to start with for jets because of the mess the previous owner has made of them. I'm gonna tear into the carb this week and I want to get a few jets ordered so I can try a few things. Also I don't have accessaccess to a manual right away so does anyone have a picture of the stock carb that they could label which screws I'm adjusting as per the instructions in the sticky?
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