Hi to all new on here with a savage 21bb/3.5 need help

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You state its 'bogging'...can you elaborate? Don't see how flush/flush can bog (cut out) unless you've got some underlying issue. Usually flush/flush is so rich it stumbles and chockes from being so rich,


Now that you are up and rolling, you should consider the tuning-method I outlined above. As noted just reply back with any issues. Of course the idle will be high when you tune it...that is what you want...as the only way to get a crisp take off with that clean puff of smoke with is to prevent the engine by loading up so you balance your LSN and idle-stop. Focus on getting better each day with your engine tune and it will make you faster-guaranteed. Said differently, go get some!
 
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One clarification above: the idle (when high) will be rough...that is normal until you finish tuning,

However, if the idle is inconsistent in that the moment you start the engines the RPMs go up and down/up and down that is potentially another issue (usually the plug or the fuel delivery system) but could be a lot of things. Easiest thing is to look for air bubbles in your fuel line,. Just did not want you to confuse that with the idle going everywhere after you release the throttle (which is almost always just your tune).
 
I'll upload a vid tomoz it bogs from stand still and then WOT. I need to give gradual throttle from take of then it's fine but still bogs / hesertates on WOT .. Got the iderling problem out the way . Adjusted the SPN to flush with the outside of housing idles fine now
 
Yeah, post up a vid if you are able, that would be awesome....I've had the exact problem quite a few times, and often a new fuel delivery system (tank/clunk/tubes) fixed the problem. Once I got cute and decided to get some colored tubing (on a Losi vehicle), but the diameter was too small..took me forever to figure out that's what it was....but it was. Of course there are so many things but hearing it I might be able to provide a little direction (I'll try to help at least).
 
Managed to get a short video today sorry about the footage I was on my own . On take off it's at WOT and bogs like a bugger but I don't ease it off tho ... Here's the link.
 
That is too lean on the lsn, richen it about 1/8 out and try again... It should transition smoothly from idle to wot, and not bog at all.....
 
Thanks for the fast reply . So would I turn the Lsn counter clockwise
 
it definitely sounds lean below, Can you show us a pic of your needle settings I appreciate you posting up a video,. As mentioned it helps. In return, would you like me to post up a video showing how I tune (as I tune it)? I I'm happy to help, Just let me know. In know reading it is one thing...seeing it certainly helps. Some of the members on here might have already posted tuning videos. I'm unsure.

But at a minimum, I can show you what the results look.sound like in each of the stages I recommended earlier: https://www.hpisavageforum.com/thre...-savage-21bb-3-5-need-help.14708/#post-183604
 
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If you could show me I would appreciate that .. I'll take a cupple pics tonight . My Lsn is not flush with the housing like its ment to be it's slightly over lapping it and will even more after I turn it anti clockwise
 
Not a problem. When I first got started, it was frustrating as everyone kept talking about how to tune, but no one would ever show me. You took the tme to post a video for us so I don't mind at all;-) Richening your LSN might correct that or it might not, but 'not bogging' and being tuned are different things. Honestly, I would not run it much like that. I;'ll have something up in the next 24 hours for ya.
 
Daz86 said:
My Lsn is not flush with the housing like its ment to be it's slightly over lapping it and will even more after I turn it anti clockwise
Click to expand...

Yeah, it's probably not just your LSN then. I have an idea what it is bu let's rule out tune first. I only listened to it at first but now just noticed all the smoke you have coming out (which is good as it helps narrow it down)

I myself have had much worse--so it's nothing to worry about. ;-) Tuning is not easy, for me it wasn't. I personally don' get caught up in needle settings or temps. They are whatever they are when the engine is tuned.

When you set it to flush screw in then out, On the LSN, keep the crb slide out as you screw in
So my questions:
.1. What type of engine is it? You put .3.5 in the title....sorry if missed it in the thread.
2, Instead of a pic, if you can do a quick vid showing the idle gap (with filter off engine of course not running) at neutral, WOT, and then back to neutral and then brake.Not so much looking for the gap opening (although I know for a fact that is one issue)...but really how the carb skide behaves during it=s cycle. If unable to no worries--but OIll ask about it later anyway, ;-)
3,. Did the truck do this previously?
4. Have you taken the engine apart at all (it's better if you did not but some things to consider if you did)
5. Turn your flywheel by hand...does the drive shaft move at the same RPMs?

Finally when you 'reset you LSN, hold the carb slide/bellow full out, screw the LSN in all the way until it gets pressue, then close the carb slide nd back it out to flush. Doesn't have be perfect....just so we have a baseline.

As noted I'm confident I can get you going strong with it....there will be a lot of things to rule out but that is the nature of it. I'll post up something in in about 12-16 hours to have you try and we go from there. Thx
 
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Thanks rick for your help so far . The engine is a nitro star 21bb .. It never bogged this much until I changed fuel types but the same % .. That's no problem making a vid I'll do it tonight straight from work . Also I have never taken the engine apart ..
 
Okay...changing % did not cause that. Unless the fuel was contaminated or spoiled on the shelf (happened to me once)....I've got a few videos to place here (in the next hour or so).

How about your clutch...when was the last time you looked at it? Did you change the bearings? IF you take the engine off....look for any oil around the flywheel nest).t on the engine plate. Simply want to make sure your front bearing is not leaking...once again I doubt it would yield such a nasty bog. Just keep up the good attiude...;lots of guys that are new get a bit freaked out like the world is ending...these engines are a lot stronger then let on to be, IMO.
 
Here you go. I am an expert ...but I was mentored by some pretty salty guys (still am to this day) so tuning is something I still work on.

1. Vid 1 I just walk through how I put a base tune on. I have plentym of part 2, part 3 etc for these videos where I go in to more detail on *proper* tuning, but a lot of those I provide to people as they ask. ;-)

I PROMISE you that when you try it things will go wrong, Don't try to get it just like mine, but please follow it so we can rule out the tune. (From there I can help you with the hard stuff.,) It looks easy, but as noted I spared everyone through the intricate things I fix along the way as that is not intended for this audience.


2. Different vehicle/engine/pipe, etc, This vid shows common albeit subtle problem. It helps ro see things your engine should not do (I can send you a lot of these ones ha ha). I caught this before going to track so rolled film to so folks can see the problem domain.

Finally: I will PM you very specific things you'll want ot know about following my process. It's not hard but strict, so I won't bore others with it all.

As noted, let me know if you have questions now, else lets get going on doing it right so you can get down with your Savage! Just takes some tenacity and an open mind to try something new, which I can sense you have,
 
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I had a look at my clutch about a week ago all looked fine no fuel or residue from what I could se .. I'm gona try your suggestions tonight
 
Okay, good ion the clutch. You stated it startd when you switched fuel %...have you tried going back to what you did run? As noted I am 99.% certain the % changre didfn't cause that, but I always going back to what the most recent change(s) were, So it was bogging a little and then you switched fuels and it is activing like this?

The puff of smoke early in the power-band made me wonder abiout the flywheel slipping but the times it's happened to me the truck didn't just look crazy rich but it acted as such too. If you have another fuel tank (any kind that you can slap on) you might try that too., My initial instincts tell me it's perhaps your fuel delivery system. Do you know how old the tank is? I've had so many problems with those...the clunk goes bad,, seams leak, and HPI's tanks are notorious for going south pretty quickly. Definitely watch the fiuel going to your engine if you can. See if it pauses and yoy get big gaps of air,. If running an inline filter, bypass iit, Check the bolts on the heat sync going in to the button head, etc. I'd rule out all that kind of stuff before cracking open the engine (or course now that I say that watch it be a bent gasket. ;-) Alsp check your ehaust gasket. Apologogies if you have already tried much of this, just thinking out loud here.

It could also be a combination of things. I doubt the re-tune will completely solve it but you have to at least rule that out, When you do get it fixed though you'll really get it ripping having learned different things to listen for, I'm still interested in the throttle and how it's opening closing as well as the gap...but often it;'s decelerationn where it bogs,. This will be fun to see you get figured out though.
 
I have already changed the fuel tank as it was leaking from the fuel primer .to a primerless tank . It made no difference
 
if you ask me it looks like you have the high needle too far screwed in, how far open is the needle ???
 
I just have to ask a couple questions here, you said flush on the hi needle yet in your video it looks to be way too far in to be flush.... how is the pinch on this engine because I am leaning to it being just plain wore out and that's 99% of your tuning issues....where is the low needle sitting in the housing ? you did not show a picture of where it is sitting at..... the idle gap looks ok to me, but without having the engine in front of me it is difficult to actually give a decent diagnosis......
 
The Hsn has never ever bean flush it's 3 tirns from fully closed the Lsn is flush with the housing .. The engine has verry good compression also no leaks . So I can't c how it would be a knackerd engine
 
I say 3 turns is too lean on the high end, it needs a bit more fuel in the transition from idle to WOT.....
 
Can yo show me where I said the Hsn was flush . The stock setting are 3 and a half turns out
 
I did not say you said flush, rickboblee did in a post above, I just think ya got it too lean up top based on a visual
 
Yes I do realize that.... sorry I am just trying to help ya here with that bogging..... and your high end does look a bit too far turned into the barrel
 
I no your trying to help . My understanding is to . Lean the Hsn to get a good top end . The stock setting are both 3 1/2 for the Hsn and the Lsn I have leaned the Hsn to 3 turns and ritchend the Lsn to 4 turns out .. Both from flush
 
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