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drz400 big bore installed starter not strong enough for raised compression ? Help

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Hi i have just installed a cylinder works 434 kit on my new to me 04 drz400s i bought it with a bad head so replaced the cylinder head with a used  04 drz400e head so it comes with the better cams and springs. while i was in there i put on the single layer gasket to raise compression even more, now that its all back together with a new charged battery it does not spin the motor fast enough to start it. usually it will turn once then just completely stop on compression stroke. i hooked it up to a car battery for more amps which helps a little but not much, it will start sometimes but only barely. if i touch the throttle at all while cranking it over it will immediately stop the starter. is normally this hard to turn over a 434 with e base gasket and e cams? when i turn the motor over with a wrench it gets really tight at compression stroke and i hear no ticking from the auto decomp  should i be hearing the tick every rotation? i do hear air leaking into the exhaust slowly and it typically will not pass the stroke unless i wait a few seconds for air to escape first. Any help would be appreciated. I just want to ride it, been wrenching and waiting on parts for months. oh it will start easily when push started at a high enough speed but tends to lock the tire up even on dry tarmac. If it makes any difference I'm using the stock bsr36 carb right now with a james dean jet kit. 

Edited by Supermotolad

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Hi i have just installed a cylinder works 434 kit on my new to me 04 drz400s i bought it with a bad head so replaced the cylinder head with a used 04 drz400e head so it comes with the better cams and springs. while i was in there i put on the single layer gasket to raise compression even more, now that its all back together with a new charged battery it does not spin the motor fast enough to start it. usually it will turn once then just completely stop on compression stroke. i hooked it up to a car battery for more amps which helps a little but not much, it will start sometimes but only barely. if i touch the throttle at all while cranking it over it will immediately stop the starter. is normally this hard to turn over a 434 with e base gasket and e cams? when i turn the motor over with a wrench it gets really tight at compression stroke and i hear no ticking from the auto decomp should i be hearing the tick every rotation? i do hear air leaking into the exhaust slowly and it typically will not pass the stroke unless i wait a few seconds for air to escape first. Any help would be appreciated. I just want to ride it, been wrenching and waiting on parts for months. oh it will start easily when push started at a high enough speed but tends to lock the tire up even on dry tarmac. If it makes any difference I'm using the stock bsr36 carb right now with a james dean jet kit.

I honestly don't know, but sounds like something's really tight in there. Ate you using a MCCT? Maybe it's super tight?

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Yeah manual adjuster but only finger tight. When I can get it to start it runs good, faster than my friends stock 400 but has no top end power, still breaking it In. I replaced the cam chain also, hope there is no difference between s and e length

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No the auto comp is still on the cam and seems to work normally in my hand springs back and pin is not dropped out. I just can't here it click when I turn the motor over with a wrench

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Every indication is that the auto decompression on the EX cam is not working.  With the top cover off, turn the motor over by hand,  You should be able to see the 

 auto decompressor contact the valve lifter and bump the right EX valve open momentarily.   What is the valve clearance on that valve?  Try setting it near the low end of the clearance spec (.008") for a little more lift.

 

The E cams do not make it harder for the starter but the 436 kit and higher compression does.  As you notice, no choke and no throttle does help out the starter.  It restricts the intake enough to limit compression.

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Yeah i thought the same but seems to work fine in my hand. My ex is at .24 and Intake .13 I re shimmed them yesterday because they were at .19 and it did same thing with hard starting. I could not see the bucket actually moving when I looked last time but I assumed it was such a small movement it was just hard to see. With a new fully charged stock battery it will turn over once then stick on next comp stroke and kill battery enough to not turn it again. Is it normal to hear the hiss for a couple of seconds on tdc compression stroke? Or should it come out fast? I'm thinking it's only partially opening

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If your auto decomp is working then your starter should have no problem turning the engine. Maybe remove your starter and disassemble it. Clean the comuntator and check the brushes

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Yeah manual adjuster but only finger tight. When I can get it to start it runs good, faster than my friends stock 400 but has no top end power, still breaking it In. I replaced the cam chain also, hope there is no difference between s and e length

Are you sure your cam timing is correct and your not like one tooth out?

BB will still pull hard up to 8K or more, not that you need too.

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I swapped the starter motor from my other Drz with no change, and have double checked the timing, my numbers are at 12 o'clock 9 and 3 with 15 pins in between. I can take a photo if it helps rule that out. Is there another ground apart from the one beside the starter?

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I swapped the starter motor from my other Drz with no change, and have double checked the timing, my numbers are at 12 o'clock 9 and 3 with 15 pins in between. I can take a photo if it helps rule that out. Is there another ground apart from the one beside the starter?

Read up here, http://www.thumpertalk.com/topic/718276-drz-valve-clearance-check-and-adjustment-plus-cam-timing/

I'm not following you on your cam setting's, lobes should be 10 and 2 @TDC

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Oh sorry I was talking about the other side, the sprockets with numbers and arrows. Lobes are at 10 and 2 yes

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I swapped the starter motor from my other Drz with no change, and have double checked the timing, my numbers are at 12 o'clock 9 and 3 with 15 pins in between. I can take a photo if it helps rule that out. Is there another ground apart from the one beside the starter?

well seeing you swapped your starter motor maybe take the one that's out and service it. You might find that both starters need a service..I have mounted my main ground cable to my starter as well

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Since you seem to know what you are doing, go back to the auto decompresser.  The de-compression devise must noticeably lift the EX valve from its seat.  Put a dial indicator on the right EX valve and measure the lift as the decompression pin passes the lifter.  I do not have a number to give you. I suspect something like .005" at least.

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Today I just wanted to ride it, and with it not wanting to start without a little gas which kills the starter I suspected the jetting or carb. Since it spins over faster with no throttle and should start without throttle. So I swapped another stock carb from my friends Drz and gave it a try. It started fine, quick and with no throttle. I stopped and started it 5 times no problems so I went for a ride and all was well for 15-20 mins until I stopped for gas. When I tried to restart it turned over fine, kept cycling without sounding weak and just never started. It bump started fine at a fast speed. So now I'm troubled again. I thought the carb somehow fixed my problem. I will do dome jetting changes and see if it helps.

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