Question about my Hensim 250???

think · 04-17-2012, 05:22 PM

Hello everyone. I've owned my Hensim 250 enduro (the green machine) for about 2 years now and it's been a really good bike until the other day while riding on a country cruise it started to lose power at high rpms and eventually stalled the engine. I got it started back up and limped it 9 of the 11 miles back home (walked it the rest :/) by feathering the clutch and shifting a lot between gears because it seemed to run well when first put into a gear but as my speed would increase in the gear it would lose power, sputter and kill the engine. Then I would have to wait awhile and try a bunch to restart it then go a few more miles. It is very strange to me and I can't seem to think of what may cause this or how to fix it. I took it home and changed the oil and checked the spark plug (seems ok). I took the carb apart and cleaned it thoroughly and put it back together. Put new gas in it. It now starts with ease and will rev up fine to full throttle while in neutral. Once I engage gears and ride it around, it does the same thing as before when I'm about 3/4 of the way through a gear's rpm range it sputters and tries to die on me... I'm lost. Would a CDI have anything to do with this? It shifts fine. It fires up and runs fine until i put it into gear and ride around. It doesn't matter what gear i'm in, it will sputter and die at a certain rpm range it seems. If anybody knows what might cause this and/or how to remedy it I would be much obliged. It's a 4 stroke honda clone engine like most of the 200's but it's a 250. Thanks in advance for any info...

FastDoc · 04-17-2012, 05:35 PM

CDI's do all sorts of weird things and is simple and cheap to replace and see. Indeed your's have lived longer than most.

I don't think it's the issue but checking your compression is reasonable also.

A clogged fuel filter or petcock could cause this quite easily. So could too low a fuel float height.

think · 04-17-2012, 05:48 PM

Thanks Doc I thought about making sure my fuel lines were unobstructed but have not done so yet.. I will Try a new CDI and cleaning my fuel filter and lines. Hopefully that will fix the problem... If not then I will try to fix compression but i'm not sure what all would be involved in doing that. New seals inside the piston chamber maybe? I don't know much about fixing an engine's compression.. I hope the CDI change will fix it... Thanks for the ideas

FastDoc · 04-17-2012, 06:16 PM

I'd check the fuel before the ignition I think that's where the problem is.

Disconnect fuel line from csarb and turn the gas on. Have a container handy. Flow should be brisk. If not there's your problem. I think this will do it.

katoranger · 04-17-2012, 07:10 PM

Quote:

Originally Posted by FastDoc

I'd check the fuel before the ignition I think that's where the problem is.

Disconnect fuel line from csarb and turn the gas on. Have a container handy. Flow should be brisk. If not there's your problem. I think this will do it.

x2. If the carb clean helped then likely its fuel related. If you still have the original china hoses it is may be time to replace. They may be dropping chunks of rubber and its plugging jets.

Try running the choke at about half way. If response improves it is most definately fuel.

Also make sure it is not leaking air between the carb and intake.

Allen

Weldangrind · 04-17-2012, 11:07 PM

These guys are giving you excellent advice. If you clean the petcock strainer and change the CDI with no joy, we'll move onto spark.

think · 04-17-2012, 11:58 PM

Thanks for all the advise, much appreciated

I have a CDI unit on the way (figure it can't hurt to have a spare) Will try the fuel line Cleaning/replacing tomorrow. Hopefully that will get me out and riding again...

culcune · 04-18-2012, 01:48 AM

I think a new spark plug couldn't hurt while you're working on the bigger stuff.

think · 04-18-2012, 12:58 PM

Well I boogered up my fuel line while trying to remove it from my inline fuel filter. So I have ordered a 1ft section of new fuel line. Now it's just a waiting game. I have a feeling it was that the fuel line was clogged because it was not free flowing when i removed it from the carb. Kinda trickling. I hope that's what it is. And yes culcune I suppose I might as well put a new plug in there while i'm at it.... So far I have a CDI, a fuel line, and a new high flow air filter ordered and on the way. I took the stock airbox off when I first got the bike and had an aftermarket ebay air filter on it. Here's a link to what I had on it http://www.ebay.com/itm/New-42mm-Air...item27c218a17c
The metal top to this thing eventually rattled off. I would not recommend this filter to anyone. With the top of of it it could have sucked stuff into the intake. I didn't ride long like this and never in dusty conditions, but who knows? Carb seemed clean when I took it apart and cleaned the jets. I'm betting it was just the fuel line being clogged that caused this trouble.... I hope i didn't suck anything into the combustion chamber. I'll post a follow up once I get everything overhauled. Hopefully it will be good news

FastDoc · 04-18-2012, 01:18 PM

I have a feeling it was that the fuel line was clogged because it was not free flowing when i removed it from the carb. Kinda trickling.

If that's not the whole problem it is certainly part of it.

China hoses are made of hollowed out Lo-mein noodles and fail nearly always.

The fact that it fell apart on removal attests to that.

Weldangrind · 04-18-2012, 10:49 PM

On an old China bike forum that no longer exists, I read that China fuel hoses are made to Canadian drinking straw specs.

think · 04-23-2012, 03:36 PM

LoL about the lo mein noodles! I certainly believe that. I got the new fuel line put on today and once I got all the air bubbles out of the line and everything it rides great. I'm almost positive that that is what it was. I'm still afraid to ride it very far without my new air filter (still waiting on the slow boat from china). But I think that the problem is solved. Thank you all for your help! I love this site

FastDoc · 04-23-2012, 03:39 PM

Happy to help.

Glad you're up and running.

And yes this is an awesome site. I love it here.

gloud · 04-23-2012, 03:54 PM

It may have been a clogged vent on the tank also. If the vent is in the cap you may or may not be able to clean it. if it happens again loosenÂthe cap on the tank and see if it helps.

SpudRider · 04-23-2012, 10:33 PM

Quote:

Originally Posted by FastDoc

Happy to help.

Glad you're up and running.

And yes this is an awesome site. I love it here.

X2 on all points.

I'm glad you got your problem fixed.

Spud

04-17-2012, 05:22 PM	#1
think Join Date: Jan 2010 Posts: 31	Question about my Hensim 250??? Hello everyone. I've owned my Hensim 250 enduro (the green machine) for about 2 years now and it's been a really good bike until the other day while riding on a country cruise it started to lose power at high rpms and eventually stalled the engine. I got it started back up and limped it 9 of the 11 miles back home (walked it the rest :/) by feathering the clutch and shifting a lot between gears because it seemed to run well when first put into a gear but as my speed would increase in the gear it would lose power, sputter and kill the engine. Then I would have to wait awhile and try a bunch to restart it then go a few more miles. It is very strange to me and I can't seem to think of what may cause this or how to fix it. I took it home and changed the oil and checked the spark plug (seems ok). I took the carb apart and cleaned it thoroughly and put it back together. Put new gas in it. It now starts with ease and will rev up fine to full throttle while in neutral. Once I engage gears and ride it around, it does the same thing as before when I'm about 3/4 of the way through a gear's rpm range it sputters and tries to die on me... I'm lost. Would a CDI have anything to do with this? It shifts fine. It fires up and runs fine until i put it into gear and ride around. It doesn't matter what gear i'm in, it will sputter and die at a certain rpm range it seems. If anybody knows what might cause this and/or how to remedy it I would be much obliged. It's a 4 stroke honda clone engine like most of the 200's but it's a 250. Thanks in advance for any info...
	0

04-17-2012, 05:35 PM	#2
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	CDI's do all sorts of weird things and is simple and cheap to replace and see. Indeed your's have lived longer than most. I don't think it's the issue but checking your compression is reasonable also. A clogged fuel filter or petcock could cause this quite easily. So could too low a fuel float height. __________________ Happy to serve.
	0

04-17-2012, 06:16 PM	#4
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	I'd check the fuel before the ignition I think that's where the problem is. Disconnect fuel line from csarb and turn the gas on. Have a container handy. Flow should be brisk. If not there's your problem. I think this will do it. __________________ Happy to serve.
	0

04-17-2012, 11:07 PM	#6
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	These guys are giving you excellent advice. If you clean the petcock strainer and change the CDI with no joy, we'll move onto spark. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

04-18-2012, 01:48 AM	#8
culcune Join Date: May 2006 Location: Yuma, Arizona Posts: 9,035	I think a new spark plug couldn't hurt while you're working on the bigger stuff. __________________ "They say that life's a carousel, spinning fast you got to ride it well..." TGB Delivery Scooter 150 TMEC 200 Enduro--carcass is sadly rotting in the backyard
	0

04-17-2012, 05:48 PM	#3
think Join Date: Jan 2010 Posts: 31	Thanks Doc I thought about making sure my fuel lines were unobstructed but have not done so yet.. I will Try a new CDI and cleaning my fuel filter and lines. Hopefully that will fix the problem... If not then I will try to fix compression but i'm not sure what all would be involved in doing that. New seals inside the piston chamber maybe? I don't know much about fixing an engine's compression.. I hope the CDI change will fix it... Thanks for the ideas
	0

04-17-2012, 11:58 PM	#7
think Join Date: Jan 2010 Posts: 31	Thanks for all the advise, much appreciated I have a CDI unit on the way (figure it can't hurt to have a spare) Will try the fuel line Cleaning/replacing tomorrow. Hopefully that will get me out and riding again...
	0

04-18-2012, 12:58 PM	#9
think Join Date: Jan 2010 Posts: 31	Well I boogered up my fuel line while trying to remove it from my inline fuel filter. So I have ordered a 1ft section of new fuel line. Now it's just a waiting game. I have a feeling it was that the fuel line was clogged because it was not free flowing when i removed it from the carb. Kinda trickling. I hope that's what it is. And yes culcune I suppose I might as well put a new plug in there while i'm at it.... So far I have a CDI, a fuel line, and a new high flow air filter ordered and on the way. I took the stock airbox off when I first got the bike and had an aftermarket ebay air filter on it. Here's a link to what I had on it http://www.ebay.com/itm/New-42mm-Air...item27c218a17c The metal top to this thing eventually rattled off. I would not recommend this filter to anyone. With the top of of it it could have sucked stuff into the intake. I didn't ride long like this and never in dusty conditions, but who knows? Carb seemed clean when I took it apart and cleaned the jets. I'm betting it was just the fuel line being clogged that caused this trouble.... I hope i didn't suck anything into the combustion chamber. I'll post a follow up once I get everything overhauled. Hopefully it will be good news
	0

04-18-2012, 01:18 PM	#10
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	I have a feeling it was that the fuel line was clogged because it was not free flowing when i removed it from the carb. Kinda trickling. If that's not the whole problem it is certainly part of it. China hoses are made of hollowed out Lo-mein noodles and fail nearly always. The fact that it fell apart on removal attests to that. __________________ Happy to serve.
	0

04-18-2012, 10:49 PM	#11
Weldangrind Join Date: Mar 2009 Location: Sardis, BC, Canada Posts: 25,977	On an old China bike forum that no longer exists, I read that China fuel hoses are made to Canadian drinking straw specs. __________________ Weldangrind "I figure I'm well-prepared for coping with a bike that comes from the factory with unresolved issues and that rewards the self-reliant owner." - Buccaneer
	0

04-23-2012, 03:36 PM	#12
think Join Date: Jan 2010 Posts: 31	LoL about the lo mein noodles! I certainly believe that. I got the new fuel line put on today and once I got all the air bubbles out of the line and everything it rides great. I'm almost positive that that is what it was. I'm still afraid to ride it very far without my new air filter (still waiting on the slow boat from china). But I think that the problem is solved. Thank you all for your help! I love this site
	0

04-23-2012, 03:39 PM	#13
FastDoc Join Date: Mar 2009 Location: Southeastern Washington desert Posts: 14,761	Happy to help. Glad you're up and running. And yes this is an awesome site. I love it here. __________________ Happy to serve.
	0

04-23-2012, 03:54 PM	#14
gloud Join Date: Sep 2011 Location: Westhampton Mass USA Posts: 155	It may have been a clogged vent on the tank also. If the vent is in the cap you may or may not be able to clean it. if it happens again loosenÂthe cap on the tank and see if it helps.
	0