locky Posted January 26, 2017 Share Posted January 26, 2017 From what I remember LSN turns is less than HSN, but will count later. https://www.rcnitrotalk.com/forum/threads/nitro-tuning-tips-and-tuning-flow-chart.60832/ 1 Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 If lean HSN need to richen LSN 1 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 Thanks will have a read through all of that. Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 (edited) Well worked out why it didn't start just as I gave up, have killed the first glow plug. Have just put a new Os no8 in it. The flow chart seems to make quite a lot of sense so will have to go through that tomorrow if it's a bit warmer. Yeah Under the flow chart the pic of the carb says the low speed should be flush, when i set it to the factory settings it is about 2-3 mm sticking out. Will making it flush be a good thing to try? Will read the rest of it tonight. Edited January 26, 2017 by Rustypeb89 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 Scrap that about the low speed being flush at factory it's just under flush not sure why I thought it was sticking out Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 My LSNs 3 to 3.5 turns out, HSN about 5 turns out, idle gap about 0.7mm eg paper clip, 25% fuel. Only tune a fully warm engine. 1 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 Thanks, Do you think its worth trying those settings? When you say warm do you mean 200f+ thats what i was trying to do. Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 In this weather run half a tank so heat fully dissipates through all internals, pre warming helps but never as good as real running, usually about 250-275F, but temps can vary due to conditions. Have you checked temps after warming, dont really want +300F for long periods. Are you doing long WOT runs or short bursts? If it's not bogging but readily revving then cutting out then richen HSN 1/2 turn at a time and LSN 1/8 turn. Leaning LSN should increase idle rpm, so shouldnt have to use the tx trim to keep idling. You need to find HSN sweet spot first, best to start rich then lean. Try those settings and see how it goes. Factory LSN setting is on the rich side so good for break in at low rpms. Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 Where measuring temps, down onto glow plug? Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 (edited) Ok thanks will do that, I was pre heating to 200 during running don't think it got much over 250 but will make sure I check temps more often. Am just doing short bursts if I held it any longer it would cut out. This is the bit which confused me it seemed to bog a bit but with very little smoke and when I let go of the throttle the revs sound high which makes me think it was lean, seemed to get better as I richened it. I have set mine to your settings, wasn't too far off them really tho the idle needed closing abit. Will use them as a starting place then try what you have said. If it keeps carrying on I will try and film it as I'm really rubbish at explaining it and probably making it more confusing then it should. Taking temps down the glow plug and one the side of the body the black bit not the blue head. Edited January 26, 2017 by Rustypeb89 Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 Sounds like too lean on HSN, revs hanging after full throttle. Could be why mine is 5 turns on HSN. 1 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 Yeah did think so think it surprised me how much richer it needed to be from what it said in the manual and everything I had watched showed it getting leaned from the factory setting not the other way around. Guessing now then when I got the HSN rich enough it messed the LSN which is why it started struggling when slower speeds. Have it set to your setting now any way and will start from there when I try next. After i I finish this half gallon of fuel I will probably be swapping brands to one I can buy locally, still the same % guessing this will affect the tune but will I have to do anything else when I swap? Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 Tuning is part of nitro running and shouldnt take too long once initial set up. Usually just minor tweaks to HSN. 1 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 Yeah understand that just need to learn more what I need to look for and listen for but that should come with time I hope. Hoping to get to a track at some point soon and hopefully will be able to see and hear what others that have it right are like in person and not just trying to get it from YouTube videos. Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 Never stop learning. If you dont fail then you arent learning, just keep trying but not the same things. Quote Link to comment Share on other sites More sharing options...
locky Posted January 26, 2017 Share Posted January 26, 2017 Never stop learning. If you dont fail then you arent learning, just keep trying but not the same things. 1 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 26, 2017 Author Share Posted January 26, 2017 Yeah very true, it is completely different to what I was used too but he been great fun and can't wait to keep learning more about it. Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 27, 2017 Author Share Posted January 27, 2017 put a couple more tanks through this morning. It is running much better on your settings, think I just had to richen the LSN I little but that was it. Didn't do much tuning as I struggled to get the engine up to temp but probably didn't help that it was 1c out side. Something didn't sound right towards the end so brought it back in thinking something is lose, have just checked it whilst on my lunch break and something is wrong in the front diff so will have to have a good clean and take that apart later, seems something has moved or stripped in the diff. Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 27, 2017 Author Share Posted January 27, 2017 One thing I did notice after a short blast of WOT the engine took a few seconds too settle back down to idle, I didn't change anything to stop this as I was trying to warm the engine still but would I need to adjust the LSN to help with this? I was getting a good amount of blue smoke at WOT. Quote Link to comment Share on other sites More sharing options...
locky Posted January 27, 2017 Share Posted January 27, 2017 Tuning is as much an art as science. I would try richening HSN first. 1 Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 27, 2017 Author Share Posted January 27, 2017 Shall do once I get the front diff fixed. Will have a practice tuning the buggy a bit more too so I know what I'm looking/listening for more. Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 27, 2017 Author Share Posted January 27, 2017 (edited) double post as the site went down again. Edited January 27, 2017 by Rustypeb89 Quote Link to comment Share on other sites More sharing options...
locky Posted January 27, 2017 Share Posted January 27, 2017 If your HSN is too lean, after a full throttle pass when you let off the throttle the engine is still lean causing the idle to hang and idle high until the LSN has a chance to take over and meter the right amount of fuel to bring the idle down to normal running speed (given the LSN is set correctly). If the opposite happens, after a full throttle pass when you let off the throttle it drops to a good idle right away and then starts to idle back up too high, this is a sign that the LSN is too lean. If it comes off full throttle with a good tune and will drop RPM nicely then the HSN is metering the fuel properly but once it hits idle the LSN being too lean will quickly take over causing the RPM to go back up. 1 Quote Link to comment Share on other sites More sharing options...
locky Posted January 27, 2017 Share Posted January 27, 2017 If your HSN is too lean, after a full throttle pass when you let off the throttle the engine is still lean causing the idle to hang and idle high until the LSN has a chance to take over and meter the right amount of fuel to bring the idle down to normal running speed (given the LSN is set correctly). If the opposite happens, after a full throttle pass when you let off the throttle it drops to a good idle right away and then starts to idle back up too high, this is a sign that the LSN is too lean. If it comes off full throttle with a good tune and will drop RPM nicely then the HSN is metering the fuel properly but once it hits idle the LSN being too lean will quickly take over causing the RPM to go back up. Quote Link to comment Share on other sites More sharing options...
Rustypeb89 Posted January 27, 2017 Author Share Posted January 27, 2017 Thanks locky, think it is defiantly too lean on the HSN then will richen it up when i get it going again and go from there. Thankfuly the diff is fine and the grub screw holding the front drive shaft on had come out but it means the lock tight I used through out the build was rubbish so will strip it down and re lock tight everything that needs it with some new stuff. Quote Link to comment Share on other sites More sharing options...
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