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PostPosted: Wed Jan 14, 2015 12:26 pm 
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Joined: Thu Apr 10, 2014 3:32 pm
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Location: Southwestern Illinois, USA
When I get my tank back from the radiator shop mine will look exactly like yours aside from the pipe, MrE. No lights, and not sure I will bother with them. Your tank looks nicer than mine. It was abandoned at my buddy's shop and got it for nothing really. Once I rebuilt the carb it fired right up on second kick- the first kick snapped the lever right back at my calf and I thought well, no need to check the compression!
Mine has a Uni foam pod on it too, but I just replaced what it came with so it must have already been jetted for it. The pipe isn't necessarily attached at the head so I have to sort that, and brake pads. Can't wait to ride it.

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1974 Honda MR175, 1974 Honda MT250, 2003 Honda CRF150, 2003 Suzuki DRZ125, 2005 KTM 250 SXF


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PostPosted: Wed Jan 14, 2015 7:23 pm 
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Joined: Sun Nov 30, 2008 12:10 pm
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Location: Connecticut, USA
Here's an old thread that might help with exhaust manifold sealing:

viewtopic.php?f=21&t=4135&hilit=91305

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Wed Jan 14, 2015 10:50 pm 
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Posts: 38
Thanks for that info Ray. I'll likely be messing with that in the next week or two when I assemble the "new" exhaust.

Tailgunn, awesome. I was pretty pleased to open my tank after getting it home and scoped it inside, found zero rust. Petcock leaked a little but I had a few spare Honda seal kits around. I'm pretty sure the front brakes are the same as xl/xr 175/250's too, so I would imagine they'd be hard to find.

I see I've got some electrical demons to exorcise on my handlebars and harness. Someone put a kill switch on it and hacked the harness for head and tail lights off. Still gotta find the speedo too. Does anyone know of a Honda speedo that will work, even if not quite correct?


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PostPosted: Thu Jan 15, 2015 7:09 am 
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Joined: Sun Nov 30, 2008 12:10 pm
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Location: Connecticut, USA
Here's a pretty decent speedo - it's identical to the '75-'76 MR175 unit:

http://www.ebay.com/itm/1976-HONDA-MR25 ... ae&vxp=mtr

Maybe the seller will throw in the mounting bracket; it may fit the MR175, or be easily modified to work.

The front and rear brake shoes are the same (P/N 06430-GBJ-J10) and are still available from Honda.

Here's a wiring diagram:

download/file.php?id=138&mode=view

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Thu Jan 15, 2015 9:17 am 
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Location: Southwestern Illinois, USA
Thanks for the exhaust info Ray. I will take a closer look at what is or is not there tonight. The pipe is hanging near the vicinity of the exhaust port but not enough to do anything besides direct the exhaust right into my lungs.

I don't have a title so it will only be a trail bike. No plans for lights or tach, but the kill switch is missing. The wiring is there though... which makes me wonder how I killed it the one time I had it running. :shock: I am watching some EBC brake shoes on ebay and I've seen a few others too. They are currently VERY spongy but I haven't really looked into the actual cause yet.

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1974 Honda MR175, 1974 Honda MT250, 2003 Honda CRF150, 2003 Suzuki DRZ125, 2005 KTM 250 SXF


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PostPosted: Thu Jan 15, 2015 10:58 am 
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Location: Connecticut, USA
If you need an exhaust manifold for the stock pipe, the MT125 and MR175 ones will both work - there are several of each on eBay now.

I've tried EBC and Vesrah aftermarket brake shoes, and I liked the OEM Hondas better (same stopping power, less fade). If your brakes are clean and lubed (use minimal grease on the pivot-shaft flats) with new shoes and they still feel spongy, it could be cable stretch or a sloppy pivot-shaft hole in the backing plate(s). I've done everything to these brakes (turned the drum, pivot-shaft bushings, lever mods, etc.) and everything makes a difference, some more than others. Bad wheel bearings can make a real difference too - I'm on my 3rd set now, mine seem to last about 3K miles.

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Mon Jan 19, 2015 9:57 am 
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Location: Southwestern Illinois, USA
I figured there wouldn't be an OEM brakes to be found but I did find some. I generally prefer OEM brakes for cars and cycles, but always used EBC on my roadracers. I printed out a fiche for the exhaust so I can see exactly what I do or don't have.

I also found a 75 cr125 basket case locally for sale. Is mostly there and has MISI swingarm? Is that something special? Missing ignition but says it's mostly there. It's in pieces. Worth pursuing?

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1974 Honda MR175, 1974 Honda MT250, 2003 Honda CRF150, 2003 Suzuki DRZ125, 2005 KTM 250 SXF


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PostPosted: Mon Jan 19, 2015 11:22 am 
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Location: Connecticut, USA
If that '75 CR rolling chassis is decent you could always the drop the MR motor in it - that's what I did with my '74 CR. It's too bad it's missing the ignition (huge upgrade for the MR) but there are usually plenty of those on eBay. I never heard of MISI - apparently they're a kart place now?

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Mon Jan 19, 2015 4:49 pm 
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Location: Southwestern Illinois, USA
Did a google for MISI, appears that some people thought they were something special but not a whole lot of info to be found. He also says ignition, oil and side number plates are missing. Not sure exactly what he means by oil. Has a non-correct gas tank too.

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1974 Honda MR175, 1974 Honda MT250, 2003 Honda CRF150, 2003 Suzuki DRZ125, 2005 KTM 250 SXF


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PostPosted: Mon Jan 19, 2015 5:07 pm 
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Location: Connecticut, USA
Maybe get it for parts? That's what I did with my MR, didn't turn out that way though. :^)

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Mon May 04, 2015 8:18 am 
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Hello again guys. I had to shelf the project for a little while and get some other stuff taken care of. But I'm back again. I see the speedo is still for sale on ebay, and a few others have popped up, so I may grab it soon. still looking for a headlight that is correct, but about to buy whatever will fit in the meantime. I missed out on a nos brake light for $90 back in Feb, dammit. I did score a $25 mt125 pipe in GREAT condition, and a little supertrapp as well. So that is in process of getting cut up at the moment. I'll likely look for a spare motor to spruce up at Mid O this year. And Ray, A friend happened on a lot of 70's "American Eagle" enduros in California a while back. I don't have the pics handy for now, but where my pipe shows cut and weld lines, it "could" (looks just like) a couple of the pipes on those old bikes. I think they used Kawasaki motors iirc.

Sort of long range here, but a friend and I are talking about prepping our bikes to do a portion of the Trans America trail next summer. He has an XL175. In proper working order, do you think this bike would be good for the Tennessee leg of the trail? So far I've only had it out for about 4 hrs at a time once a month on fire trails and such.


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PostPosted: Tue May 05, 2015 3:59 pm 
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Location: Connecticut, USA
I'd never heard of American Eagles - apparently they were built near Birmingham, U.K.:

http://www.earlyyearsofmx.com/Americaneagle.html

What a strange brew of components, but hey, it was the Sixties. :)

Three of those headlights sold over the last week or so (two MR250's and a TL250 unit) so they do show up on eBay - hang in there, you'll find one.

From the description of the Trans-American Trail ride (http://www.transamtrail.com/the-trans-am-trail), it seems like something that's tailor-made for larger dual-sport and adventure bikes, not vintage 175's. I think you'd find the XL underpowered and under-suspended for it even with a bigger fuel tank, but I've never been on it and can't speak from experience.

Ray

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Sun May 10, 2015 8:50 pm 
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Yes, after looking into the trail a bit more it seems a bit ambitious for some vintage dirt bikes. But, I do ride my 75 cb750 600+ miles on trips (i say that and it will probably fall apart on my next trip).

Yesterday I noticed another issue. My air/fuel screw came out somewhere on the trail. Looking on eBay found only one , and it was $40 used. Got me to thinking if another carb may be an alternative that I can still buy reasonable parts for. I saw another thread from a few years ago where a lady mentioned using a 26mm mikuni... No model number or anything given. But then in the old hop up articles on this site I see a 34mm mikuni from sudco mentioned as a good one. Any direction on that?


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PostPosted: Mon May 11, 2015 5:09 am 
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Location: Connecticut, USA
The hollow MR175 air screw has a wide adjustment range and works well if the center's clear, but I wouldn't pay $40 even for a new one.

This carb kit is pretty good, and very reasonable for all you get with it:
http://www.ebay.com/itm/HONDA-FL250-ODY ... 03&vxp=mtr

I wouldn't use the pilot jet as it's way too rich (a #48 is much better), but everything else should work well. If you change the idle speed screw be careful, there's a small brass collar in the carb body that loves to fall out, and if it does the idle speed will be erratic.

Ray

Link to the pilot jets (this place has the 99101-357 main jets too):
http://jetsrus.com/a_jets_by_carburetor ... 29-xxx.htm

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'74 CR125M (175cc), '75 MR175, '82 RM250Z, '08 YZ250F, '14 Zero FX electric, '14 Zero MX electric, '18 Alta MXR electric


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PostPosted: Mon May 11, 2015 9:52 am 
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Joined: Wed Jul 27, 2011 12:31 pm
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Thanks, Ray. Been doing some more reading also on these and it seems as though the Keihin PE28 is a "modern" version of the stock carb. Also the PWK 28. I guess what I'm driving at is in my quest to get the old girl reliable I'm wanting to get to as much off the shelf new stuff as I can. I did go ahead and order the kit you posted (Thanks!) but i'm wondering if long term it wouldn't be a bad idea to spring for a completely fresh carb. I'm also keeping an eye out for a new jug/piston this summer. hoping to finish up the mt125/supertrapp exhaust tonight for it. I have been seeing the headlights for the 250's once in a while, I'd just really love to find the correct metal caged light for my year if possible. For now I've got a little trail 70 speedo/light combo stuck on it. Speedo cable should be in today, so hoping it "kinda" works even though I know the ratio will be way off. Long term I probably wont be going back 100% original though. just reliable and clean.


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