fastforworddad Posted August 23, 2012 Author Report Share Posted August 23, 2012 Big red has an idea there. If the small hose from the the little nipple on the head, I call it the steam port, is clogged, it could be getting vapor locked from steam build up in the head I would imagine and would cause irratic temperatures. There are always hot spots that can create the steam in the head, that's what that hose vents to the top of the radiator. Yeah I thought about that, when head was removed the hose was clear and the port was clear also. Keep the ideas coming. When I took the head off, the domes showed no detonation and were clean with only an oily residue on the surface that wiped clean. Pistons too were pretty clean, no signs of detonation and only minimal carbon on piston crowns. I will try and get some pics when I get back home. It is my understanding that there should be carbon on domes and crowns, please correct me if I am wrong. I have maybe 25-30 hours on fresh cub build. Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 23, 2012 Author Report Share Posted August 23, 2012 Big red has an idea there. If the small hose from the the little nipple on the head, I call it the steam port, is clogged, it could be getting vapor locked from steam build up in the head I would imagine and would cause irratic temperatures. There are always hot spots that can create the steam in the head, that's what that hose vents to the top of the radiator. Yeah I have my stocker I can swap back in. I know I am somewhat fat on jetting but wouldn't have thought it would make it run this hot. Always thought lean is where the heat is. Hell I don't know anymore, got a bike that i can ride in 8 minute burst, then gotta let it cool off. Well it is a good 8 minutes though!!! Trying to stay positive. Question In a perfectly jetted bike, when the head is removed, should there be carbon on domes and piston crowns? Quote Link to comment Share on other sites More sharing options...
toytech Posted August 23, 2012 Report Share Posted August 23, 2012 Yeah I have my stocker I can swap back in. I know I am somewhat fat on jetting but wouldn't have thought it would make it run this hot. Always thought lean is where the heat is. Hell I don't know anymore, got a bike that i can ride in 8 minute burst, then gotta let it cool off. Well it is a good 8 minutes though!!! Trying to stay positive. Question In a perfectly jetted bike, when the head is removed, should there be carbon on domes and piston crowns? you will have some carbon or oil build up but not much, I would think rich should run cooler. I like the idea of putting the stock rad back in and trying it, because high speed use, over heating tells me the rad isn't doing it's job correctly, I've seen some new rads that in the welding prosese the tubes partialy colapse and will not cool good. but the coolant still looks like it's flowing good. I had this happen on my race car with a very good rad builder,they exchanged it problem solved for me. Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 23, 2012 Author Report Share Posted August 23, 2012 you will have some carbon or oil build up but not much, I would think rich should run cooler. I like the idea of putting the stock rad back in and trying it, because high speed use, over heating tells me the rad isn't doing it's job correctly, I've seen some new rads that in the welding prosese the tubes partialy colapse and will not cool good. but the coolant still looks like it's flowing good. I had this happen on my race car with a very good rad builder,they exchanged it problem solved for me. I will put stocker back in but will probably have to buy another head since the Noss bottom half has to be forced down over studs while the top half slides right over the studs. Definitely would be a problem having to tap bottom half on over studs and trying to keep domes and all the o rings in place. What I don't understand is that if I put a fan in front of radiator at idle it cools just fine. Temps are hot here and humidity is too, but there are several bikes here running the dunes while I have to watch cause bike is too hot. Sad thing is, alot of the bikes I have seen here have been rode hard and put up wet. I take care of my bike almost to a fault, cleaned after every ride, chain cleaned and lubed, all zerks wiped off then greased, then area is wiped again to clean of excess grease. Just ranting a little bit. We will figure it out. Thanks guys. Wayne Quote Link to comment Share on other sites More sharing options...
camatv Posted August 23, 2012 Report Share Posted August 23, 2012 if the cub is a 68mm bore you cannot put the stock oem head on it unless it has been machined for the bore. if the bike showed high temps but didnt overheat, didnt overflow, and seemed to run ok, then seemed to cool down quickly ( i'm guessing the 250+ degrees was intermitent like after a long pull up a dune then at the top on the way down they went back do to the 220 ish range) in very high ambient temps i'd say you dont have a problem... a pump gas cub in 115* ambient temps running flat out is probably going to get pretty hot. try putting the OEM radiator back in. use a 60 + mix of coolant and water ( more coolant %) if you stop to let the bike cool down running at idle its not going to cool the radiator. (no air flow) what about the fans you were talking about? have you had a chance to run those yet. are you reading the temp from the motor before the rad or after the rad into the motor ( cooled temps) Quote Link to comment Share on other sites More sharing options...
georgie Posted August 23, 2012 Report Share Posted August 23, 2012 Is it possible you got the water pump gear on the crank backwards? Sounds like you got no coolant flowing. Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 23, 2012 Author Report Share Posted August 23, 2012 if the cub is a 68mm bore you cannot put the stock oem head on it unless it has been machined for the bore. if the bike showed high temps but didnt overheat, didnt overflow, and seemed to run ok, then seemed to cool down quickly ( i'm guessing the 250+ degrees was intermitent like after a long pull up a dune then at the top on the way down they went back do to the 220 ish range) in very high ambient temps i'd say you dont have a problem... a pump gas cub in 115* ambient temps running flat out is probably going to get pretty hot. try putting the OEM radiator back in. use a 60 + mix of coolant and water ( more coolant %) if you stop to let the bike cool down running at idle its not going to cool the radiator. (no air flow) what about the fans you were talking about? have you had a chance to run those yet. are you reading the temp from the motor before the rad or after the rad into the motor ( cooled temps) Yeah, I was running pretty fast slowing down to see the itty bitty trail tech temp gauge, then back up to speed, last stop was 256*F or very close to that. So parked in a very slight breeze and waited for everyone else to turn around and get back to me. When I shut it off, i would let the temp drop some on the gauge, then I would start it up to circulate some of the cooler coolant into engine, then shut it off and repeat. Had a problem with the fan controller, got another one on the way. The temp sender for the trail tech is right out of the head. I am going to get a infrared thermometer to try and get a DT. Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 23, 2012 Author Report Share Posted August 23, 2012 Is it possible you got the water pump gear on the crank backwards? Sounds like you got no coolant flowing. Its possible, I will check it when I get home. Thanks Wayne Thought about it, the crank water pump gear can go on either way can't it? Quote Link to comment Share on other sites More sharing options...
ginger Posted August 23, 2012 Report Share Posted August 23, 2012 it wouldnt have the notches for that pin to make the gear and shaft spin. Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 24, 2012 Author Report Share Posted August 24, 2012 it wouldnt have the notches for that pin to make the gear and shaft spin. I was talking about the one that is on the crank, the gear you are talking about rides on it. Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 27, 2012 Author Report Share Posted August 27, 2012 Put the head back on last night, had a couple bent studs, replaced them and the NOSS slid over studs pretty smoothly. Started right up as it always does. Will probably take it out later today or tomorrow Didn't see anything wrong with it when apart so hoping for the best and preparing for the worst, worst being same result. Any other ideas please chime in. Quote Link to comment Share on other sites More sharing options...
robert0762 Posted August 27, 2012 Report Share Posted August 27, 2012 I have been chasing temps for a long time now and finally figured out what my problem was. I have oversize impellar and dad. I had timing set at +5 such was my prob. Put it at 4 and still getting hotter then it should. Went to 3 and she runs at 180 now even running hard it won't see 190. Just try it Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 27, 2012 Author Report Share Posted August 27, 2012 I have been chasing temps for a long time now and finally figured out what my problem was. I have oversize impellar and dad. I had timing set at +5 such was my prob. Put it at 4 and still getting hotter then it should. Went to 3 and she runs at 180 now even running hard it won't see 190. Just try it Thanks bro, will try it tomorrow, boy I sure hope that is it. Thanks again Wayne Quote Link to comment Share on other sites More sharing options...
ITFD Posted August 28, 2012 Report Share Posted August 28, 2012 Did you remove the hoses that go from the rad to the motor at all? If you removed the hoses at the motor end you may have reversed them? Just a thought.. Chek all your plumbing. The bypass and overflow tubes on the rad maybe reversed? Got to be something simple!! Quote Link to comment Share on other sites More sharing options...
fastforworddad Posted August 28, 2012 Author Report Share Posted August 28, 2012 Did you remove the hoses that go from the rad to the motor at all? If you removed the hoses at the motor end you may have reversed them? Just a thought.. Chek all your plumbing. The bypass and overflow tubes on the rad maybe reversed? Got to be something simple!! Yes, the hoses have been separated from engine and radiator several times, but rerouted per Clymer's manual. Let me ask just to be sure... The steam hose, the one out of the head goes to the radiator--fastens to nipple opposite of the cap and overflow goes fastens to nipple at cap. Coolant hose out of head goes to top of radiator and the one at the water pump goes on the bottom. I think Robert may be on to something with the timing, I will be trying that today. I would be happy to give up some timing for a coloer running bike even though I am only at +4. Thanks bro. Quote Link to comment Share on other sites More sharing options...
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