DisTech's DR350 rebuild

Progress is looking REALLY good. You'll be happy to know that the old battered clarke tank you gave me is now on it's way up to Alaska all the way to the north slope aboard a buddy's DR350. I'm currently holed up in Mexico and bikeless. Would you mind taking a couple of measurements for me on your WP forks? I need to get the leg ODs at both the upper and lower clamping surfaces and also the center to center leg spacing if possible. Yes, those headlights are awesome. Don't expect oncoming traffic to appreciate them though. I get brights flashed at me CONSTANTLY.

Thanks. I was wondering if I'd ever here if that tank helped anyone.

WP forks and triples are from a 2007 KTM 200xc (in case you find an actual data sheet)
upper triple clamp od: 54mm
lower triple clamp od: 60mm
center to center: 191.75mm

WARNING: I triple checked the measurements, but tequila absolves me of all responsibilities!

I love the 8" HID and for commuting it's pointed at the ground in front of the bike. So far, no problem.

Hmmm. Someone else told me the leg spacing is 190. Weird. Exactly how much tequila have you had? Any chance of getting a couple decimal places on the diameters? Thanks man. Glad to see you overcame your initial engine troubles.

Great thread. Just thought I'd share this. If you are in a bind to cool the bearings down or want to cool them instantly, a can of Dust-Off air spray works great. Invert the can and spray. The propellant is well cold enough to freeze things instantly.

I just finished reading the build. Outstanding work. Now I'm going back to read your DR650 build again. Cheers! (And nice choice on the vodka!)

The can of air is a good idea. Thanks!

Found a guy selling 5 sticks of HTS-2000 on ebay for $8. Wish I would have seen that before I bought the Muggy Weld stuff. Anyway, with this stuff if you watch there video they join two flat pieces of metal by tinning both sides and then sticking them together. I did that with the oil cooler outlets and AN connectors, tinned both sides and stuck them together. The joints have much better penetration than the Muggy Weld did, but this is the last try for brazing. If these joints fail I'll pay someone to tig weld them.

Awesome job on the re build. Thats the best looking dr I think I've ever seen.


Think the only thing I'd change is the front fender to a white Ktm model as that acerbis one looks to be pointing a little high to me.

But honestly. Awesome job.... I'm inspired

DisTech,

The trail tech X2 light looked good but the TT Race light looks BAD ASS!!! great job on your build.

Cheers,

Cumbacheech

Thanks man! I know what you mean about it pointing kinda high. I hope the HID doesn't melt it.

Yes it does! Ha! Thanks, gonna use the X2 on the estart model when I get to it.

Ok.. got so inspired by your build. I picked up a dr 350s cheap.. owner couldn't get it started so I did a little barter job.. think over all it was gas money to get there and no money out of pocket.

cleaned the carb. did a little self priming and 30 kicks later.. she runs..

orderd a pumper carb and now working on acquiring parts.

Maybe I'll pull out the old XR 650r Rally Fairing molds and see what I can fab up of the DR



though I picked up cheap.. I've already spent $400 on carb, dirt rear shock and extra parts.. sourcing front USD forks.. but going keep it within the year so I can possibly race NORRA on it.. but we'll see.

Kind of a jumbled mega post, but a couple people asked for it. So, here we go!

The Jetting Guide: The Yamaha / Keihin FCR Carburetor at thumperfaq.com is very helpful for tuning and links to all kinds of FCR mods. One popular mod is disabling the Air Cut Valve (ACV). The ACV is one of the reasons I wanted a FCR (reduce popping on decel), but during jetting some recommend disabling it and that's what's going on in this picture. I blocked the vacuum passage with an almost round piece of rubber (11oclock from the diaphragm). You can also see my "plate" (3oclock from the diaphragm) in place of the unused Throttle Position Sensor (TPS).


thumperfaq.com's guide reference the WR250F owners manual because it has a good tuning guide. I found the full manual online and hacked it down and indexed it just for the FCR stuff, 2001 WR250F User Manual (Keihin FCR-MX37 only).

mxrob.com has a wealth of info about installing an FCR-MX39 on a DR650, but a lot applies to the FCR-MX37 on a DR350 as well. I've got the Merge Racing AP spring installed but still need to adjust the AP timing.

Composite picture from the WR250F manual. It shows all the jets and labels them with normal names. It's much better than the exploded view from Sudco.


To understand the how to order jets for the FCR I downloaded the monster 244mb 2011 Sudco Main Catalog No. 36 and made a mini index to look at while paging around in the big file.

Description...............................Page (pdf page)
FCR-MX Standard Jetting Specifications....27 (14)
FCR-MX Rebuild Kits...................... 28 (15)
FCR-MX Replacement Parts (and index)......29 (15)
jet needles...............................31 (16)
main jets.................................62 (32)
main air jets.............................62 (32)
slow jet..................................60 (31)
starter jet...............................62 (32)
slow air jet..............................60 (31)

The following jet lists are from the catalog.

Sudco name........Keihin FCR-MX Slow N424-21-XXX
Normal name.......Pilot Jet (PJ)
jet...............part number
#35...............019-005
#38...............019-006
#40...............019-007
#42...............019-008
#45...............019-009
#48...............019-010
#50...............019-011
#52...............019-012
#55...............019-013
#58...............019-014
#60...............019-015
#62...............019-016
#65...............019-017
#68...............019-018
#70...............019-019
#72...............019-020
#75...............019-021
#78...............019-022
#80...............019-023

Sudco name........Keihin FCR Slow Air Jet 99101-124-XXX (99101-ZF5-XXX)
Normal name.......Pilot Air Jet (PAJ)
jet...............part number
#48...............019-402
#50...............019-403
#52...............019-404
#55...............019-405
#58...............019-406
#60...............019-407
#62...............019-408
#65...............019-409
#68...............019-410
#70...............019-411
#72...............019-412
#75...............019-413
#78...............019-414
#80...............019-415
#82...............019-416
#85...............019-417
#88...............019-418
#90...............019-419
#92...............019-420
#95...............019-421
#98...............019-422
#100..............019-423
#102..............019-424
#105..............019-425
#108..............019-426
#110..............019-427
#112..............019-428
#115..............019-429
#118..............019-430
#120..............019-431
#122..............019-432
#125..............019-433
#128..............019-434
#130..............019-435
#135..............019-437
#140..............019-439
#145..............019-441
#150..............019-443

Sudco name........Keihin FCR-MX Main Jet 99101-357-XXX
Normal name.......Main Jet (MJ)
jet...............part number
#80...............019-101
#82...............019-102
#85...............019-103
#88...............019-104
#90...............019-105
#92...............019-106
#95...............019-107
#98...............019-108
#100..............019-109
#102..............019-110
#105..............019-111
#108..............019-112
#110..............019-113
#112..............019-114
#115..............019-115
#118..............019-116
#120..............019-117
#122..............019-118
#125..............019-119
#128..............019-120
#130..............019-121
#132..............019-122
#135..............019-123
#138..............019-124
#140..............019-125
#142..............019-126
#145..............019-127
#148..............019-128
#150..............019-129
#152..............019-130
#155..............019-131
#158..............019-132
#160..............019-133
#162..............019-150
#165..............019-134
#168..............019-151
#170..............019-135
#172..............019-152
#175..............019-136
#178..............019-153
#180..............019-137
#182..............019-154
#185..............019-138
#188..............019-155
#190..............019-139
#195..............019-141
#200..............019-143
#205..............019-145
#210..............019-147
#215..............019-149
#220..............019-702
#230..............019-704

Sudco name........Keihin FCR Main Air Jet 99101-393-XXX
Normal name.......Main Air Jet (MAJ)
Sudco name........Keihin FCR-MX Starter Jet 99101-393-XXX
Normal name.......Starter Jet
jet...............part number
#60...............019-710
#62...............019-711
#65...............019-712
#68...............019-713
#70...............019-714
#72...............019-715
#75...............019-716
#78...............019-717
#80...............019-718
#82...............019-719
#85...............019-720
#88...............019-721
#90...............019-174
#92...............019-175
#95...............019-176
#98...............019-177
#100..............019-178
#102..............019-179
#105..............019-180
#108..............019-181
#110..............019-182
#112..............019-183
#115..............019-184
#118..............019-185
#120..............019-186
#122..............019-187
#125..............019-188
#128..............019-189
#130..............019-190
#132..............019-191
#135..............019-192
#138..............019-193
#140..............019-194
#142..............019-195
#145..............019-196
#148..............019-197
#150..............019-198
#152..............019-199
#155..............019-200
#158..............019-201
#160..............019-202
#162..............019-203
#165..............019-204
#168..............019-205
#170..............019-206
#172..............019-207
#175..............019-208
#178..............019-209
#180..............019-210
#182..............019-211
#185..............019-212
#188..............019-213
#190..............019-214
#192..............019-215
#195..............019-216
#198..............019-217
#200..............019-218
The Main Air Jet and the Starter Jet are from the same series.

Sudco name........OEM FCR-MX Leak Jet N424-52-XXX
Normal name.......Leak Jet
jet...............part number
#35...............019-750
#38...............019-751
#40...............019-752
#42...............019-753
#45...............019-754
#48...............019-755
#50...............019-756
#52...............019-757
#55...............019-758
#58...............019-759
#60...............019-760
#62...............019-761
#65...............019-762
#68...............019-763
#70...............019-764
#72...............019-765
#75...............019-766
#78...............019-767
#80...............019-768
#82...............019-769
#85...............019-770
#88...............019-771
#90...............019-772
#92...............019-773
#95...............019-774
#98...............019-775
#100..............019-776
#102..............019-777
#105..............019-778
#108..............019-779
#110..............019-780
#112..............019-781
#115..............019-782
#118..............019-783
#120..............019-784
#122..............019-785
#125..............019-786
#128..............019-787
#130..............019-788
#132..............019-789
#135..............019-790
#138..............019-791
#140..............019-792

Not knowing anything about the carb's history, I wanted a rebuild kit and found Power-Barn.com had a good selection and good prices.
Sudco FCR-MX Carburetor Rebuild Kit FCR-MX....020-319

Rebuild kit and Merge APS.


To assemble a jet kit, Jets R Us is the bomb! They have genuine Keihin jets and in many cases OEM equivalent jets at less than half the price. From the jet kit I assembled you can tell what I was planning to tinker with.

Pilot Jet (PJ).........#40*, #42, #45, #48, #50
Pilot Air Jet (PAJ)....#75*, #100
Main Jet (MJ)..........#148, #150, #152, #155, #160*
Main Air Jet (MAJ).....#200*
Starter Jet............#72*
Leak Jet...............#52, #55, #58, #60*
*......................Already had that size, didn't need to order

Now for the secret sauce!

Jetting as the FCR came from ebay from a 2001 WR250R.
Main Jet (MJ)..........160
Main Air Jet (MAJ).....200
Pilot Jet (PJ).........40
Pilot Air Jet (PAJ)....75
Starter Jet............72
Leak Jet...............60
Needle Clip............3rd position
Pilot Screw............not listed

Default jetting according to big catalog No. 36.
Main Jet (MJ)..........160
Main Air Jet (MAJ).....200
Pilot Jet (PJ).........45
Pilot Air Jet (PAJ)....100
Starter Jet............not listed
Leak Jet...............not listed
Needle Clip............3rd position
Pilot Screw............not listed

slowsuki
Main Jet (MJ)..........150
Main Air Jet (MAJ).....none
Pilot Jet (PJ).........48
Pilot Air Jet (PAJ)....100
Starter Jet............none
Leak Jet...............55
Needle Clip............3rd position
Pilot Screw............3 1/4 turns from closed

My current jetting
Main Jet (MJ)..........150
Main Air Jet (MAJ).....200
Pilot Jet (PJ).........42
Pilot Air Jet (PAJ)....100
Starter Jet............72
Leak Jet...............55
Needle Clip............3rd position
Pilot Screw............2 turns from closed

Starts with a couple kicks. Still don't have much actual ride time, but I think I'm close overall. Need to re-enable the ACV.

Thanks again to slowsuki for putting me in the ball park, huge time saver.

Ran through all the gears to make sure I had all the forks and cams where they should be.



should it be easy to run through all the gears as the assy sits in the casing only held by one end?? mine is at this stage but it is not shifting very easy through the gears ??

No, on their sides the forks don't shift real smooth and the fork shafts move a little with only one end in place. I had to jiggle the fork shafts sometimes to get it to run through the gears.

However, when you put the case back together they should run through the gears real easy. If they don't, something is wrong. Be careful assembling the case halves, all it takes is a small drop of case sealant in the wrong spot (on one of the fork shafts) to gum up the gears and the case has to come apart again (ask my how I know).

I had the same problem... I could not get the tranny to shift through the gears without the case halves together. Once together, everything worked great.

On a similar issue, when I downshift from 3rd, my bike frequently skips 2nd and goes into neutral. Anyone else having this problem? (Sorry about the hijack, but I know there are a lot of knowledgeable people here)

Haven't ridden enough, but during break in I didn't notice it skipping from 3rd to neutral.

i would look around the star shaped bit by the selector drum or the sprin on the wheel that it rides on ?? ,
maybe the gear on the end of the gear shaft is missaligned with the gear on the end of the selector drum??
p.s. just put some new pics of my progress up

Hey man just put my case together, noticed some end float in the crank shaft main bearings. Is this normal?

This is an awesome build and you now have a couple of great bikes that are individual and have your own personal touch.

Back in 1990 I bought a DR250S brand new, this was my first bike. I had it for 8 years and put 70,000 very memorable kilometres on that bike (thats about 45,000 miles for you americans).

All these years later I'm back on Suzuki's with a DRZ400E and RMX250 in my shed. I have considered selling the DRZ and doing a 350 project like yours. I think the 6 speed makes them a better all round bike than the DRZ. Your project has defiantly got me thinking.

Thanks for sharing your work, great project.

I don't know. Saw you posted in your thread also, hope someone can help.

Thank you, looking forward to your build.

I'm currently working on the suspension. The WP forks have been rebuilt and resprung and the shock has a RaceTech GoldValve and shim kit. For the shock I have a stock spring (5.8k/mm), an Eibach 5.8k/mm and an Eibach 8.1k/mm spring. I need a 6.1k/mm spring, but they have been discontinued. RaceTech only gives you five minutes with their online shim calc program so you can't play with it. SOOooo... I bought Shim ReStackor and have been working my way through the math... making progress but the rusty wheels don't turn so easy anymore!

What do you think of these spring rates? And if you don't mind me asking, what do you weight, and what kind of riding are you setting the bike up for?

I assume my bike has the stock spring rate, but I'm not real sure. Whatever it is, it's way to soft for me, and that's weird, because RaceTech recommends an even softer spring for me.